Physics and Technology of Semiconductor Quantum Nanostructures
Lead Research Organisation:
University of Cambridge
Department Name: Physics
Abstract
We are accustomed to the use of electricity in every day life, this is based on the flow of electrons through materials which have a high conductivity such as metals. At low temperatures the laws of quantum mechanics prevail and now an electron does not behave as a particle but rather as a wave, which reflects the probability of finding an electron in a particular place. An entirely new range of phenomena flow from this change in the physics and this is most pronounced in very small devices, called nanostructures. The purpose of this grant is to enable the most advanced nanostructures to be fabricated and new physical phenomena to be sought in them. In addition to the new physics that will be found, new methods of transmitting and handling data will emerge, which will be of great benefit to both existing and future industries yet to be born.
Publications
Das Gupta K
(2011)
Experimental Progress towards Probing the Ground State of an Electron-Hole Bilayer by Low-Temperature Transport
in Advances in Condensed Matter Physics
Sarkozy S
(2009)
Low temperature transport in undoped mesoscopic structures
in Applied Physics Letters
Pfaendler S
(2008)
Stable conductance plateaus from ridge wires grown on a patterned substrate
in Applied Physics Letters
Schneble R
(2006)
Quantum-dot thermometry of electron heating by surface acoustic waves
in Applied Physics Letters
Astley M
(2006)
Examination of surface acoustic wave reflections by observing acoustoelectric current generation under pulse modulation
in Applied Physics Letters
Ferrus T
(2010)
Disorder and electron interaction control in low-doped silicon metal-oxide-semiconductor field effect transistors
in Applied Physics Letters
Goswami S
(2010)
Thermoelectric properties of electrostatically tunable antidot lattices
in Applied Physics Letters
Chen T
(2008)
Bias-controlled spin polarization in quantum wires
in Applied Physics Letters
Huang D
(2008)
Effects of inelastic capture, tunneling escape, and quantum confinement on surface acoustic wave-dragged photocurrents in quantum wells
in Journal of Applied Physics
Kataoka M
(2006)
The effect of pulse-modulated surface acoustic waves on acoustoelectric current quantization
in Journal of Applied Physics
Astley M
(2008)
Quantized acoustoelectric current in an InGaAs quantum well
in Journal of Applied Physics
Wright S
(2011)
Single- and few-electron dynamic quantum dots in a perpendicular magnetic field
in Journal of Applied Physics
Narayan V
(2012)
Evidence of Novel Quasiparticles in a Strongly Interacting Two-Dimensional Electron System: Giant Thermopower and Metallic Behaviour
in Journal of Low Temperature Physics
Sfigakis F
(2008)
Spin effects in one-dimensional systems
in Journal of Physics: Condensed Matter
Chen TM
(2010)
Direct observation of nonequilibrium spin population in quasi-one-dimensional nanostructures.
in Nano letters
McNeil RP
(2010)
Localized magnetic fields in arbitrary directions using patterned nanomagnets.
in Nano letters
Blumenthal M
(2007)
Gigahertz quantized charge pumping
in Nature Physics
Siegert C
(2007)
The possibility of an intrinsic spin lattice in high-mobility semiconductor heterostructures
in Nature Physics
Clarke W
(2007)
Impact of long- and short-range disorder on the metallic behaviour of two-dimensional systems
in Nature Physics
Giblin S
(2010)
An accurate high-speed single-electron quantum dot pump
in New Journal of Physics
Danneau R
(2008)
0.7 Structure and zero bias anomaly in one-dimensional hole systems
in Physica E: Low-dimensional Systems and Nanostructures
Das Gupta K
(2008)
Selective breakdown of quantum Hall edge states and non-monotonic Coulomb drag in a GaAs-AlGaAs electron-hole bilayer
in Physica E: Low-dimensional Systems and Nanostructures
Kataoka M
(2008)
Investigation of single-electron dynamics in tunnelling between zero- and one-dimensional states
in Physica E: Low-dimensional Systems and Nanostructures
Sfigakis F
(2010)
Benefits of using undoped GaAs/AlGaAs heterostructures: A case study of the zero-bias bias anomaly in quantum wires
in Physica E: Low-dimensional Systems and Nanostructures
Croxall A
(2010)
Towards the ground state of an electron-hole bilayer
in Physica E: Low-dimensional Systems and Nanostructures
Keogh J
(2006)
Closely spaced, independently contacted electron-hole bilayers in GaAs-AlGaAs heterostructures
in Physica E: Low-dimensional Systems and Nanostructures
Kataoka M
(2006)
Single-electron transfer between double quantum dots defined by surface acoustic waves
in Physica E: Low-dimensional Systems and Nanostructures
Baenninger M
(2008)
Quantisation of hopping magnetoresistance prefactor in strongly correlated two-dimensional electron systems
in Physica E: Low-dimensional Systems and Nanostructures
Kataoka M
(2008)
Electron population control of a highly isolated quantum dot using surface-acoustic waves
in Physica E: Low-dimensional Systems and Nanostructures
Astley M
(2008)
Measurement of Coulomb-energy-dependent tunnelling rates in surface-acoustic-wave-defined dynamic quantum dots
in Physica E: Low-dimensional Systems and Nanostructures
Wright S
(2008)
Enhanced current quantization in high-frequency electron pumps in a perpendicular magnetic field
in Physical Review B
Astley M
(2006)
Examination of multiply reflected surface acoustic waves by observing acoustoelectric current generation under pulse modulation
in Physical Review B
Wright S
(2009)
Parallel quantized charge pumping
in Physical Review B
Goswami S
(2011)
Signatures of an anomalous Nernst effect in a mesoscopic two-dimensional electron system
in Physical Review B
Siegert C
(2008)
Effect of a perpendicular magnetic field on the zero-bias anomaly in two-dimensional electron systems
in Physical Review B
Croxall A
(2009)
Possible effect of collective modes in zero magnetic field transport in an electron-hole bilayer
in Physical Review B
Schneble R
(2007)
Collapse of nonequilibrium charge states in an isolated quantum dot using surface acoustic waves
in Physical Review B
Chen T
(2009)
Odd-even spin effects and variation of g factor in a quasi-one-dimensional subband
in Physical Review B
Siegert C
(2008)
Oscillatory Hall effect in high-mobility two-dimensional electron gases
in Physical Review B
Baenninger M
(2008)
Magnetic-field-induced instabilities in localized two-dimensional electron systems
in Physical Review B
Koushik R
(2011)
Evidence of gate-tunable topological excitations in two-dimensional electron systems
in Physical Review B
Chen T
(2009)
Non-Kondo zero-bias anomaly in quantum wires
in Physical Review B
Kataoka M
(2006)
Experimental investigation of the surface acoustic wave electron capture mechanism
in Physical Review B
Rushforth A
(2006)
Fano effect and Kondo effect in quantum dots formed in strongly coupled quantum wells
in Physical Review B
Hickey M
(2007)
Strongly bias-dependent spin injection from Fe into n -type GaAs
in Physical Review B
Smith L
(2009)
Row coupling in an interacting quasi-one-dimensional quantum wire investigated using transport measurements
in Physical Review B
Graham A
(2007)
Energy-level pinning and the 0.7 spin state in one dimension: GaAs quantum wires studied using finite-bias spectroscopy
in Physical Review B
Sarkozy S
(2009)
Zero-bias anomaly in quantum wires
in Physical Review B
Ho L
(2008)
Effect of screening long-range Coulomb interactions on the metallic behavior in two-dimensional hole systems
in Physical Review B
Description | The work discovered a number of unexpected features of spin polarisation and difference in energy between the different spin directions. It was found possible to induce a coincidence in energy between the spin directions by means of a magnetic field which produced a number of spin instabilities. We developed an electron pump which delivered a quantised current near nanoamps which is within range of highly accurate measurements of electron charge by standards laboratories. |
Exploitation Route | Many groups worldwide are using the patterned gate techniques which we developed. The electron pump has been taken up by standards laboratories including NPL with whom we have a good collaboration. |
Sectors | Digital/Communication/Information Technologies (including Software),Electronics,Energy |
URL | http://www.electronicsweekly.com/news/research-news/device-rd/cambridge-team-closer-to-working-quantum-computer-2007-04/ |
Description | Theory of Electron Transport in Semiconductor Nanostructures and Collaborative Experiments |
Organisation | University of Liverpool |
Department | Department of Physics |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Collaboration and explanation of experiments as well as suggestions of new experiments. These collaborations started before this award but are ongoing and have contributed to the work in the award. |
Collaborator Contribution | Many ideas and experimental contributions. Allocation of a Dilution Refrigerator in Cape Town for the experimental programme. Dr Blumenthal who is now in CapeTown took a Ph.D in Cambridge and was supervised by Pepper, he is now a lecturer there and has allocated a dilution refrigerator to our collaboration on electron pumps. We have an excellent collaboration with the Taiwan group which has provided new insights into spin-orbit coupling. The Bar Ilan and CUNY collaborations are in the area of theory and have produced some important insights into the behaviour of electrons in nanostructures which is continuing. |
Impact | 4 good publications |
Description | Theory of Electron Transport in Semiconductor Nanostructures and Collaborative Experiments |
Organisation | University of Liverpool |
Department | Department of Physics |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Collaboration and explanation of experiments as well as suggestions of new experiments. These collaborations started before this award but are ongoing and have contributed to the work in the award. |
Collaborator Contribution | Many ideas and experimental contributions. Allocation of a Dilution Refrigerator in Cape Town for the experimental programme. Dr Blumenthal who is now in CapeTown took a Ph.D in Cambridge and was supervised by Pepper, he is now a lecturer there and has allocated a dilution refrigerator to our collaboration on electron pumps. We have an excellent collaboration with the Taiwan group which has provided new insights into spin-orbit coupling. The Bar Ilan and CUNY collaborations are in the area of theory and have produced some important insights into the behaviour of electrons in nanostructures which is continuing. |
Impact | 4 good publications |
Description | Theory of Electron Transport in Semiconductor Nanostructures and Collaborative Experiments |
Organisation | University of the Balearic Islands |
Department | Physics |
Country | Spain |
Sector | Academic/University |
PI Contribution | Collaboration and explanation of experiments as well as suggestions of new experiments. These collaborations started before this award but are ongoing and have contributed to the work in the award. |
Collaborator Contribution | Many ideas and experimental contributions. Allocation of a Dilution Refrigerator in Cape Town for the experimental programme. Dr Blumenthal who is now in CapeTown took a Ph.D in Cambridge and was supervised by Pepper, he is now a lecturer there and has allocated a dilution refrigerator to our collaboration on electron pumps. We have an excellent collaboration with the Taiwan group which has provided new insights into spin-orbit coupling. The Bar Ilan and CUNY collaborations are in the area of theory and have produced some important insights into the behaviour of electrons in nanostructures which is continuing. |
Impact | 4 good publications |
Description | Theory of Electron Transport in Semiconductor Nanostructures and Collaborative Experiments |
Organisation | University of the Balearic Islands |
Department | Physics |
Country | Spain |
Sector | Academic/University |
PI Contribution | Collaboration and explanation of experiments as well as suggestions of new experiments. These collaborations started before this award but are ongoing and have contributed to the work in the award. |
Collaborator Contribution | Many ideas and experimental contributions. Allocation of a Dilution Refrigerator in Cape Town for the experimental programme. Dr Blumenthal who is now in CapeTown took a Ph.D in Cambridge and was supervised by Pepper, he is now a lecturer there and has allocated a dilution refrigerator to our collaboration on electron pumps. We have an excellent collaboration with the Taiwan group which has provided new insights into spin-orbit coupling. The Bar Ilan and CUNY collaborations are in the area of theory and have produced some important insights into the behaviour of electrons in nanostructures which is continuing. |
Impact | 4 good publications |