| 1. |
- Adamyan, Astghik, 1984, et al.
(författare)
-
Kinetic inductance as a microwave circuit design variable by multilayer fabrication
- 2015
-
Ingår i: Superconductor Science and Technology. - : IOP Publishing. - 0953-2048 .- 1361-6668. ; 28:8
-
Tidskriftsartikel (refereegranskat)abstract
- We report on the development of a reliable NbN/Al/Nb/NbN multilayer fabrication technique for combining design elements with and without kinetic inductance in superconducting microwave circuits. As a proof-of-concept we demonstrate the application of the proposed technique to build a slow microwave propagation line matched to 50 Ω terminals. Fabrication details along with the design and measurements are discussed. At 8 GHz the presented device operates as a dc controllable full-turn phase shifter. We suggest that by exploiting the kinetic inductance as a design variable one can greatly improve operation parameters for a variety of standard microwave designs such as step-impedance filters and resonators.
|
|
| 2. |
- Adamyan, Astghik, 1984, et al.
(författare)
-
Superconducting microwave parametric amplifier based on a quasi-fractal slow propagation line
- 2016
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 119:8
-
Tidskriftsartikel (refereegranskat)abstract
- Quantum limited amplifiers are sought after for a wide range of applications within quantum technologies and sensing. One promising candidate is the travelling wave parametric amplifier which exploits the non-linear kinetic inductance of a superconducting transmission line. This type of microwave amplifier promises to deliver a high gain, a quantum limited noise performance over several GHz bandwidth, and a high dynamic range. However, practical realizations of this type of device have so far been limited by fabrication defects, since the length of the superconducting transmission line required for achieving substantial parametric gain is on the order of similar to 1m. Here, we report on a design for a microwave traveling wave amplifier based on a slow propagation line comprising a central strip with high kinetic inductance and quasi-fractal line-to-ground capacitors. Due to an enhanced per unit length inductance (73 nH cm(-1)) and capacitance (15 pF cm(-1)), the line has a microwave propagation velocity as low as 9.8 x 10(8) cm s(-1). This translates into parametric gain up to 0.5 dB cm(-1) and a total gain of 6 dB for just a similar to 10 cm long transmission line. Moreover, the flexibility of the presented design allows balancing the line inductance and capacitance in order to keep the characteristic impedance close to 50 Omega and to suppress standing waves, both factors being essential in order to implement a practical parametric amplifier in the microwave domain.
|
|
| 3. |
- Adamyan, Astghik, 1984, et al.
(författare)
-
Tunable superconducting microstrip resonators
- 2016
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 108:17
-
Tidskriftsartikel (refereegranskat)abstract
- We report on a simple yet versatile design for a tunable superconducting microstrip resonator. Niobium nitride is employed as the superconducting material and aluminum oxide, produced by atomic layer deposition, as the dielectric layer. We show that the high quality of the dielectric material allows to reach the internal quality factors in the order of Q(i) similar to 10(4) in the single photon regime. Q(i) rapidly increases with the number of photons in the resonator N and exceeds 10(5) for N similar to 10 - 50. A straightforward modification of the basic microstrip design allows to pass a current bias through the strip and to control its kinetic inductance. We achieve a frequency tuning delta f = 62 MHz around f(0) = 2.4 GHz for a fundamental mode and delta f = 164MHz for a third harmonic. This translates into a tuning parameter Q(i)delta f/f(0) = 150. The presented design can be incorporated into essentially any superconducting circuitry operating at temperatures below 2.5K.
|
|
| 4. |
- Bott, Lukas Thomas, et al.
(författare)
-
Coulomb dissociation of O-16 into He-4 and C-12
- 2023
-
Ingår i: NUCLEAR PHYSICS IN ASTROPHYSICS - X, NPA-X 2022. - : EDP Sciences. - 2100-014X. ; 279
-
Konferensbidrag (refereegranskat)abstract
- We measured the Coulomb dissociation of O-16 into He-4 and C-12 within the FAIR Phase-0 program at GSI Helmholtzzentrum fur Schwerionenforschung Darmstadt, Germany. From this we will extract the photon dissociation cross section O-16(alpha,gamma)C-12, which is the time reversed reaction to C-12(alpha,gamma)O-16. With this indirect method, we aim to improve on the accuracy of the experimental data at lower energies than measured so far. The expected low cross section for the Coulomb dissociation reaction and close magnetic rigidity of beam and fragments demand a high precision measurement. Hence, new detector systems were built and radical changes to the (RB)-B-3 setup were necessary to cope with the high-intensity O-16 beam. All tracking detectors were designed to let the unreacted O-16 ions pass, while detecting the C-12 and He-4.
|
|
| 5. |
- Broman, S. L., et al.
(författare)
-
Dihydroazulene Photoswitch Operating in Sequential Tunneling Regime: Synthesis and Single-Molecule Junction Studies
- 2012
-
Ingår i: Advanced Functional Materials. - : Wiley. - 1616-3028 .- 1616-301X. ; 22:20, s. 4249-4258
-
Tidskriftsartikel (refereegranskat)abstract
- Molecular switches play a central role for the development of molecular electronics. In this work it is demonstrated that the reproducibility and robustness of a single-molecule dihydroazulene (DHA)/vinylheptafulvene (VHF) switch can be remarkably enhanced if the switching kernel is weakly coupled to electrodes so that the electron transport goes by sequential tunneling. To assure weak coupling, the DHA switching kernel is modified by incorporating p-MeSC6H4 end-groups. Molecules are prepared by Suzuki cross-couplings on suitable halogenated derivatives of DHA. The synthesis presents an expansion of our previously reported brominationeliminationcross-coupling protocol for functionalization of the DHA core. For all new derivatives the kinetics of DHA/VHF transition has been thoroughly studied in solution. The kinetics reveals the effect of sulfur end-groups on the thermal ring-closure of VHF. One derivative, incorporating a p-MeSC6H4 anchoring group in one end, has been placed in a silver nanogap. Conductance measurements justify that transport through both DHA (high resistivity) and VHF (low resistivity) forms goes by sequential tunneling. The switching is fairly reversible and reenterable; after more than 20 ON-OFF switchings, both DHA and VHF forms are still recognizable, albeit noticeably different from the original states.
|
|
| 6. |
- Burnett, J., et al.
(författare)
-
PC2: Identifying noise processes in superconducting resonators
- 2013
-
Ingår i: 2013 IEEE 14th InternationalSuperconductive Electronics Conference, ISEC 2013. - 9781467363716 ; , s. Art. no. 6604284-
-
Konferensbidrag (refereegranskat)abstract
- Extensive studies of dielectric loss due to two level fluctuators (TLFs) in superconducting resonators have provided routes for low loss resonators. The research is motivated not only by the use of resonators as detectors and in quantum information processing, but more generally due to TLFs being a source of noise and decoherence in all quantum devices. In this work a frequency locked loop was used to measure frequency fluctuations at timescales in excess of 104 seconds, thereby accurately probing the TLF induced low- frequency noise of the resonator. Our measurement method lead to very high statistical confidence even for very long timescales, and here we can therefore present results explicitly identifying power dependent flicker frequency noise (S = 1/fa where a=1) persisting down to the mHz level.
|
|
| 7. |
|
|
| 8. |
- Christensen, M. A., et al.
(författare)
-
Mixed valence radical cations and intermolecular complexes derived from indenofluorene-extended tetrathiafulvalenes
- 2014
-
Ingår i: Journal of Materials Chemistry C. - : Royal Society of Chemistry (RSC). - 2050-7526 .- 2050-7534. ; 2:48, s. 10428-10438
-
Tidskriftsartikel (refereegranskat)abstract
- Engineering of mixed-valence (MV) radical cations and intermolecular complexes based on pi-extended tetrathiafulvalenes (TTFs) is central for the development of organic conductors. On another front, redox-controlled dimerization of radical cations has recently been recognized as an important tool in supramolecular chemistry. Here we show that pi-extended TTFs based on the indenofluorene core, prepared by Horner-Wadsworth-Emmons reactions, undergo reversible and stepwise one-electron oxidations and that the detectable, intermediate radical cation forms remarkably strong intermolecular MV ([neutral.cation]) and pi-dimer ([cation.cation]) complexes with near-infrared radical cation absorptions. The radical cation itself seems to be a so-called Class III MV species in the Robin-Day classification. The formation of MV dimers was corroborated by ESR spectroelectrochemical studies, revealing two slightly different ESR signals upon oxidation, one assigned to the MV dimer and the other to the cation monomer. Crystals of the radical cation with different anions (PF6- , BF4-, and TaF6-) were grown by electrocrystallization. Conductance studies revealed that the salts behave as semiconductors with the hexafluorotantalate salt exhibiting the highest conductance. Using a custom-built ESR spectrometer with sub-femtomole sensitivity, the magnetic properties of one crystal were investigated. While the spin-to-spin interaction between radical cations was negligible, a high cooperativity coupling to the microwave field was observed - as a result of an exceptionally narrow spin line width and high spin density. This could have great potential for applications in quantum computation where crystalline spin ensembles are exploited for their long coherence times.
|
|
| 9. |
|
|
| 10. |
- Danilov, Andrey, 1961, et al.
(författare)
-
Electronic transport in single molecule junctions: Control of the molecule-electrode coupling through intramolecular tunneling barriers
- 2008
-
Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6992 .- 1530-6984. ; 8:1, s. 1-5
-
Tidskriftsartikel (refereegranskat)abstract
- We report on single molecule electron transport measurements of two oligophenylenevinylene (OPV3) derivatives placed in a nanogap between gold (Au) or lead (Pb) electrodes in a field effect transistor device. Both derivatives contain thiol end groups that allow chemical binding to the electrodes. One derivative has additional methylene groups separating the thiols from the delocalized pi-electron system. The insertion of methylene groups changes the open state conductance by 3-4 orders of magnitude and changes the transport mechanism from a coherent regime with finite zero-bias conductance to sequential tunneling and Coulomb blockade behavior.
|
|
| 11. |
- Danilov, Andrey, 1961, et al.
(författare)
-
Nanoelectromechanical switch operating by tunneling of an entire C-60 molecule
- 2008
-
Ingår i: Nano Letters. - 1530-6992 .- 1530-6984. ; 8:8, s. 2393-2398
-
Tidskriftsartikel (refereegranskat)abstract
- We present a solid state single molecule electronic device where switching between two states with different conductance happens predominantly by tunneling of an entire C-60 molecule. This conclusion is based on a novel statistical analysis of similar to 10(5) switching events. The analysis yields (i) the relative contribution of tunneling, current induced heating and thermal fluctuations to the switching mechanism, (ii) the voltage dependent energy barrier (similar to 100-200 meV) separating the two states of the switch and (iii) the switching attempt frequency, omega(0) corresponding to a 2.8 meV mode, which is most likely rotational.
|
|
| 12. |
- Danilov, Andrey, 1961
(författare)
-
Quench-Condensed Metallic Clusters Studied by Single Electron Tunneling
- 2002
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Using angle deposition through conventional electron-beam lithographic masks as the sample resistance was measured in situ, we defined constrictions with widths and lengths of about 5 nm in thin (1-3) nm granular films. The nominal film thickness in the constriction could be varied stepwise by in situ film depositions, changing the grain size and the configuration of the tunneling paths. As the film thickness was increased, the multigrain structure in constriction was replaced by a Single Electron Transistor (SET) with a single island dominating in the current transport. Despite the random nature of cluster formation, samples with periodic gate dependency and well-formed Coulomb diamonds were routinely obtained in every experimental run. The first implementation of this method resulted in a room-temperature operating SET. At helium temperatures this method allows to isolate a single cluster in a Quench-Condensed (QC) film and to fabricate, in a controllable way, SET transistors with charging energies up to 100 meV. The main result of this thesis is that the QC clusters are not frozen; their shape is self-adjusted to minimize the electronic energy. As a result, the cluster's shape is sensitive to the electrostatic and thermal perturbations. We observed a reversible temperature-driven distortion of QC clusters at temperatures below ~ 7 K. This effect is attributed to a phase transition in bismuth clusters of a new type, with the cluster shape as the order parameter. At zero temperature the cluster is deformed due to spontaneous distortion of the ground state, and above the transition temperature the thermal perturbation recovers the spherical symmetry. The electron energy dependence on the cluster distortion implies that not all quantum states in QC cluster are chaotic. This conclusion is further supported by the observation of resonances in tunneling spectra taken on a single bismuth cluster placed in a well-defined SET geometry.
|
|
| 13. |
- Danilov, Andrey, 1961, et al.
(författare)
-
Single molecular devices with fullerenes and oligophenylenevinylene (OPV) derivatives
- 2005
-
Ingår i: IEEE INTERNATIONAL ELECTRON DEVICES MEETING 2005, TECHNICAL DIGEST. - 078039268X ; , s. 481-484
-
Konferensbidrag (refereegranskat)abstract
- We have studied low temperature electron transport in three terminal single molecule transistors. Devices with OPV revealed a relation between transistor characteristics and position of molecular redox potentials strongly influenced by proximity to the metal. Fullerene based devices demonstrate negative differential resistance and indicate strong coupling of fullerene to gold.
|
|
| 14. |
|
|
| 15. |
- Danilov, Andrey, 1961, et al.
(författare)
-
Switching Mechanisms in Molecular Switches
- 2016
-
Ingår i: Handbook of Single-Molecule Electronics; ed. by Kasper Moth-Poulsen. - 9789814463393 ; , s. 263-298
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Molecular electronics aims at using tailor-built molecules as active device elements to achieve the desired electronic functionality. Molecular-based electronic switches appear to be the most promising candidates for compact memory arrays with low power consumption. In the past decade, detailed investigations have been performed on a great variety of molecular switches, including mechanically interlocked switches, conformational switches, and redox-active molecules. In this chapter, we will review basic switching mechanisms in molecular switches: thermal fluctuations, current-induced excitations, and quantum tunneling. We will demonstrate how the quantitative information allowing to judge between those different switching mechanisms can be extracted from the data measured on single-molecule devices. We will also discuss how the intrinsic switching properties may be affected when the molecule is bridged to electrodes, and how to distinguish whether the switching happens in molecular kernel or at the molecule-to-electrode interface.
|
|
| 16. |
- de Graaf, Sebastian Erik, 1986, et al.
(författare)
-
A near-field scanning microwave microscope based on a superconducting resonator for low power measurements
- 2013
-
Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 1089-7623 .- 0034-6748. ; 84:2, s. 023706-
-
Konferensbidrag (refereegranskat)abstract
- We report on the design and performance of a cryogenic (300 mK) near-field scanning microwave microscope. It uses a microwave resonator as the near-field sensor, operating at a frequency of 6 GHz and microwave probing amplitudes down to 100 μV, approaching low enough photon population (N ∼ 1000) of the resonator such that coherent quantum manipulation becomes feasible. The resonator is made out of a miniaturized distributed fractal superconducting circuit that is integrated with the probing tip, micromachined to be compact enough such that it can be mounted directly on a quartz tuning-fork, and used for parallel operation as an atomic force microscope (AFM). The resonator is magnetically coupled to a transmission line for readout, and to achieve enhanced sensitivity we employ a Pound-Drever-Hall measurement scheme to lock to the resonance frequency. We achieve a well localized near-field around the tip such that the microwave resolution is comparable to the AFM resolution, and a capacitive sensitivity down to 6.4 × 10−20 F/rtHz, limited by mechanical noise. We believe that the results presented here are a significant step towards probing quantum systems at the nanoscale using near-field scanning microwave microscopy.
|
|
| 17. |
- de Graaf, Sebastian Erik, 1986, et al.
(författare)
-
Accurate Real-Time Monitoring of Quality Factor and Center Frequency of Superconducting Resonators
- 2014
-
Ingår i: IEEE Transactions on Applied Superconductivity. - : Institute of Electrical and Electronics Engineers (IEEE). - 1558-2515 .- 1051-8223. ; 24:6
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we track both center frequency and quality factor of a superconducting microwave resonator with very high precision using a modified Pound-Drever-Hall frequency locking scheme. The quality factor measurements can be done with high enough bandwidth to study different processes in a superconducting resonator in real time. With this added functionality, the frequency readout remains unaffected, with typical accuracy around 10-30 Hz/root Hz, whereas the cavity loss rate can be determined to within 0.1% on a millisecond time scale (34 dB/root Hz). As we demonstrate, this can be particularly useful for electron spin resonance measurements, where we achieve a minimum number of detectable spins coupled to the resonator N = 5 . 10(5) spins/root Hz, based on quality factor measurements. It also enables the study of fast dynamic processes, for example, vortex dynamics, in these devices on a short time scale.
|
|
| 18. |
- de Graaf, Sebastian Erik, 1986, et al.
(författare)
-
Charge Qubit Coupled to an Intense Microwave Electromagnetic Field in a Superconducting Nb Device: Evidence for Photon-Assisted Quasiparticle Tunneling
- 2013
-
Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 111:13, s. Art. no. 137002-
-
Tidskriftsartikel (refereegranskat)abstract
- We study a superconducting charge qubit coupled to an intensive electromagnetic field and probe changes in the resonance frequency of the formed dressed states. At large driving strengths, exceeding the qubit energy-level splitting, this reveals the well known Landau-Zener-Stückelberg interference structure of a longitudinally driven two-level system. For even stronger drives, we observe a significant change in the Landau-Zener-Stückelberg pattern and contrast. We attribute this to photon-assisted quasiparticle tunneling in the qubit. This results in the recovery of the qubit parity, eliminating effects of quasiparticle poisoning, and leads to an enhanced interferometric response. The interference pattern becomes robust to quasiparticle poisoning and has a good potential for accurate charge sensing.
|
|
| 19. |
- de Graaf, Sebastian Erik, 1986, et al.
(författare)
-
Coherent interaction with two-level fluctuators using near field scanning microwave microscopy
- 2015
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 5
-
Tidskriftsartikel (refereegranskat)abstract
- Near field Scanning Microwave Microscopy (NSMM) is a scanning probe technique that non-invasively can obtain material properties on the nano-scale at microwave frequencies. While focus has been on developing room-temperature systems it was recently shown that this technique can potentially reach the quantum regime, opening up for applications in materials science and device characterization in solid state quantum information processing. In this paper we theoretically investigate this new regime of NSMM. Specifically we show that interaction between a resonant NSMM probe and certain types of two-level systems become possible when the NSMM probe operates in the (sub-) single photon regime, and we expect a high signal-to-noise ratio if operated under the right conditions. This would allow to detect single atomic material defects with energy splittings in the GHz range with nano-scale resolution, provided that individual defects in the material under study are well enough separated. We estimate that this condition is fulfilled for materials with loss tangents below tan delta similar to 10(-3) which holds for materials used in today's quantum circuits and devices where typically tan delta
|
|
| 20. |
- de Graaf, Sebastian Erik, 1986, et al.
(författare)
-
Direct Identification of Dilute Surface Spins on Al2 O3: Origin of Flux Noise in Quantum Circuits
- 2017
-
Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 118:5, s. 057703-
-
Tidskriftsartikel (refereegranskat)abstract
- An on-chip electron spin resonance technique is applied to reveal the nature and origin of surface spins on Al2O3. We measure a spin density of 2.2×1017 spins/m2, attributed to physisorbed atomic hydrogen and S=1/2 electron spin states on the surface. This is direct evidence for the nature of spins responsible for flux noise in quantum circuits, which has been an issue of interest for several decades. Our findings open up a new approach to the identification and controlled reduction of paramagnetic sources of noise and decoherence in superconducting quantum devices.
|
|
| 21. |
- de Graaf, Sebastian Erik, 1986, et al.
(författare)
-
Galvanically split superconducting microwave resonators for introducing internal voltage bias
- 2014
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 104:5, s. art no 052601 -
-
Tidskriftsartikel (refereegranskat)abstract
- We present the design and performance of high-Q superconducting niobium nitride microwave resonators intended for use in hybrid quantum systems, coupling spin degrees of freedom to the cavity mode, both magnetically and electrically. We demonstrate a solution that allows to introduce static electric fields in the resonator without compromising the microwave performance. Quality factors above 10(5) remain unchanged in strong applied static electric fields above 10 MV/m and magnetic fields up to similar to 400 mT. By design, the configuration of the dc field matches that of the microwave field, especially advantageous for experiments on electrostatically controlled spin systems.
|
|
| 22. |
- de Graaf, Sebastian Erik, 1986, et al.
(författare)
-
Magnetic field resilient superconducting fractal resonators for coupling to free spins
- 2012
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 112:12, s. 123905-
-
Tidskriftsartikel (refereegranskat)abstract
- We demonstrate a planar superconducting microwave resonator intended for use in applications requiring strong magnetic fields and high quality factors. In perpendicular magnetic fields of 20 mT, the niobium resonators maintain a quality factor above 25 000 over a wide range of applied powers, down to single photon population. In parallel field, the same quality factor is observed above 160 mT, the field required for coupling to free spins at a typical operating frequency of 5 GHz. We attribute the increased performance to the current branching in the fractal design. We demonstrate that our device can be used for spectroscopy by measuring the dissipation from a pico-mole of molecular spins.
|
|
| 23. |
- de Graaf, Sebastian Erik, 1986, et al.
(författare)
-
Quantifying dynamics and interactions of individual spurious low-energy fluctuators in superconducting circuits
- 2021
-
Ingår i: Physical Review B. - 2469-9969 .- 2469-9950. ; 103:17
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding the nature and dynamics of material defects in superconducting circuits is of paramount importance for improving qubit coherence and parameter stability and much needed for implementing large-scale quantum computing. Here we present measurements on individual highly coherent environmental two-level systems (TLS). We trace the spectral diffusion of specific TLS and demonstrate that it originates from the TLS coupling to a small number of low energy incoherent fluctuators. From the analysis of these fluctuations, we access the relevant parameters of low energy fluctuators: Dipole moments, switching energies, and, more importantly, interaction energies. Our approach opens up the possibility of deducing the macroscopic observables in amorphous glassy media from direct measurements of local fluctuator dynamics at the microscopic level- A route towards substantiating commonly accepted, but so far phenomenological, models for the decohering environment.
|
|
| 24. |
- de Graaf, Sebastian Erik, 1986, et al.
(författare)
-
Scaling of self-stimulated spin echoes
- 2024
-
Ingår i: Applied Physics Letters. - 0003-6951 .- 1077-3118. ; 124:2
-
Tidskriftsartikel (refereegranskat)abstract
- Self-stimulated echoes have recently been reported in the high cooperativity and inhomogeneous coupling regime of spin ensembles with superconducting resonators. In this work, we study their relative amplitudes using echo-silencing made possible by a fast frequency tunable resonator. The highly anisotropic spin linewidth of Er3+ electron spins in the CaWO4 crystal also allows to study the dependence on spin-resonator ensemble cooperativity. It is demonstrated that self-stimulated echoes primarily result from a combination of two large control pulses and the echo preceding it.
|
|
| 25. |
- de Graaf, Sebastian Erik, 1986, et al.
(författare)
-
Suppression of low-frequency charge noise in superconducting resonators by surface spin desorption
- 2018
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723 .- 2041-1723. ; 9:1
-
Tidskriftsartikel (refereegranskat)abstract
- Noise and decoherence due to spurious two-level systems located at material interfaces are long-standing issues for solid-state quantum devices. Efforts to mitigate the effects of two-level systems have been hampered by a lack of knowledge about their chemical and physical nature. Here, by combining dielectric loss, frequency noise and on-chip electron spin resonance measurements in superconducting resonators, we demonstrate that desorption of surface spins is accompanied by an almost tenfold reduction in the charge-induced frequency noise in the resonators. These measurements provide experimental evid ence that simultaneously reveals the chemical signatures of adsorbed magnetic moments and highlights their role in generating charge noise in solid-state quantum devices.
|
|
