| 31. |
- Ganjipour, Bahram, et al.
(författare)
-
GaSb nanowire single-hole transistor
- 2011
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 99:26
-
Tidskriftsartikel (refereegranskat)abstract
- We present an experimental study of single hole transistors (SHTs) made from p-type GaSb nanowires. Closely spaced source-drain electrodes are fabricated onto GaSb nanowires to define a SHT within a GaSb nanowire. Room temperature back-gate transfer characteristics show typical hole transport behavior. The fabricated devices are characterized by transport measurements at 1.5 K, where periodic conductance oscillations due to Coulomb blockade are observed and a charging energy of 5 meV is determined. (C) 2011 American Institute of Physics. [doi:10.1063/1.3673328]
|
|
| 32. |
- Gustafson, Boel, et al.
(författare)
-
Coupling between lateral modes in a vertical resonant tunneling structure
- 2002
-
Ingår i: Physica E: Low-Dimensional Systems and Nanostructures. - 1386-9477. ; 13:2-4, s. 950-953
-
Tidskriftsartikel (refereegranskat)abstract
- We present experimental results and theoretical calculations of the vertical electron transport through a laterally constricted resonant tunneling transistor. Current-voltage measurements at 4.2 K show numerous current peaks that exhibit a complex dependence on the applied gate voltage. A scattering-matrix approach combined with the Landauer formalism was used to perform quantum mechanical calculations of the electron transport through a quantum dot structure with laterally confined emitter and collector regions. The simulations qualitatively reproduce the measured data, suggesting a strong coupling between the lateral modes in the quantum dot and the collector
|
|
| 33. |
- Håkanson, Ulf, et al.
(författare)
-
Photon mapping of single quantum dots by scanning tunneling microscopy induced luminescence spectroscopy
- 2002
-
Ingår i: 7th International Conference on Nanometer-Scale Science and Technology and 21st European Conference on Surface Science.
-
Konferensbidrag (refereegranskat)abstract
- Scanning tunneling microscopy induced luminescence (STML) has been used to investigate individual self-assembled InP quantum dots overgrown with GaInP. We will present results correlating the surface morphology with the optical properties of single dots. In particular, the strain induced energy-shift of the dot emission with increasing cap layer thickness and its relation to the overgrowth will be discussed. Effects of the dots on the properties of the overgrown GaInP will also be treated. STML spectra and monochromatic photon maps are compared with results from photoluminescence and transmission electron microscopy measurements. Furthermore, a comparison with theoretical calculations is made
|
|
| 34. |
- Håkanson, Ulf, et al.
(författare)
-
Single InP/GaInP quantum dots studied by scanning tunneling microscopy and scanning tunneling microscopy induced luminescence
- 2002
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 80:3, s. 494-496
-
Tidskriftsartikel (refereegranskat)abstract
- We have studied the optical and structural properties of single, self-assembled InP quantum dots (QDs) overgrown with nominally 5 nm of GaInP, using an ultrahigh-vacuum scanning tunneling microscope (STM) operating at low temperatures. The STM is combined with an optical detection system, which allows us to detect the emission from individual quantum dots with high spatial resolution. We find that the InP QDs act as nucleation points for the GaInP overgrowth, where the strain induced by the overlayer give rise to a QD emission around 1.46 eV. (C) 2002 American Institute of Physics.
|
|
| 35. |
- Håkanson, Ulf, et al.
(författare)
-
Ultrahigh vacuum scanning probe investigations of metal induced void formation in SiO2/Si(111))
- 2002
-
Ingår i: JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B. - : American Vacuum Society. - 1071-1023 .- 1520-8567. ; 20:1, s. 226-229
-
Konferensbidrag (refereegranskat)abstract
- Using scanning electron microscopy guidance, atomically resolved scanning tunneling microscopy investigations inside openings formed during the decomposition of a thick SiO2 film on a Si(111) surface have been performed. We report, for the first time, the presence of Ni atoms inside self-formed openings. The SiO2 decomposition as a function of annealing temperature and time was studied. By comparing self-formed and lithographically designed openings in the SiO2 layer we have shown that Ni contamination of the SiO2/Si(111) has a profound effect on the formation of self-induced lateral oxide openings. (C) 2002 American Vacuum Society.
|
|
| 36. |
- Hällström, Waldemar, et al.
(författare)
-
Fifteen-Piconewton Force Detection from Neural Growth Cones Using Nanowire Arrays
- 2010
-
Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6992 .- 1530-6984. ; 10:3, s. 782-787
-
Tidskriftsartikel (refereegranskat)abstract
- We used epitaxially grown monodisperse nanowire arrays to measure cellular forces with a spatial resolution of 1 mu m. Nerve cells were cultured on the array and cellular forces were calculated from the displacement of the nanowire tips. The measurements were done in situ on live cells using confocal microscopy, Forces down to 15 pN were measured on neural growth cones, showing that this method can be used to study the Fine details of growth-cone dynamics.
|
|
| 37. |
- Hällström, Waldemar, et al.
(författare)
-
Gallium phosphide nanowires as a substrate for cultured neurons
- 2007
-
Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6992 .- 1530-6984. ; 7:10, s. 2960-2965
-
Tidskriftsartikel (refereegranskat)abstract
- Dissociated sensory neurons were cultured on epitaxial gallium phosphide (GaP) nanowires grown vertically from a gallium phosphide surface. Substrates covered by 2.5 mu m long, 50 nm wide nanowires supported cell adhesion and axonal outgrowth. Cell survival was better on nanowire substrates than on planar control substrates. The cells interacted closely with the nanostructures, and cells penetrated by hundreds of wires were observed as well as wire bending due to forces exerted by the cells.
|
|
| 38. |
|
|
| 39. |
|
|
| 40. |
|
|
