semiconductor heterostructure; diamond; spin qubit; laser spectroscopy; spin resonance; quantum dot; photonics; spin; semiconductor
Greuter Lukas, Starosielec Sebastian, Najer Daniel, Ludwig Arne, Duempelmann Luc, Rohner Dominik, Warburton Richard J. (2014), A small mode volume tunable microcavity: Development and characterization, in APPLIED PHYSICS LETTERS
, 105(12), 121105.
Houel Julien, Prechtel Jonathan H., Kuhlmann Andreas V., Brunner Daniel, Kuklewicz Christopher E., Gerardot Brian D., Stoltz Nick G., Petroff Pierre M., Warburton Richard J. (2014), High Resolution Coherent Population Trapping on a Single Hole Spin in a Semiconductor Quantum Dot, in PHYSICAL REVIEW LETTERS
, 112(10), 107401.
Munsch Mathieu, Wuest Gunter, Kuhlmann Andreas V., Xue Fei, Ludwig Arne, Reuter Dirk, Wieck Andreas D., Poggio Martino, Warburton Richard J. (2014), Manipulation of the nuclear spin ensemble in a quantum dot with chirped magnetic resonance pulses, in NATURE NANOTECHNOLOGY
, 9(9), 671-675.
Heath Robert M., Tanner Michael G., Casaburi Alessandro, Webster Mark G., Alvarez Lara San Emeterio, Jiang Weitao, Barber Zoe H., Warburton Richard J., Hadfield Robert H. (2014), Nano-optical observation of cascade switching in a parallel superconducting nanowire single photon detector, in APPLIED PHYSICS LETTERS
, 104(6), 063503.
Montinaro Michele, Wuest Gunter, Munsch Mathieu, Fontana Yannik, Russo-Averchi Eleonora, Heiss Martin, Morral Anna Fontcuberta I., Warburton Richard J., Poggio Martino (2014), Quantum Dot Opto-Mechanics in a Fully Self-Assembled Nanowire, in NANO LETTERS
, 14(8), 4454-4460.
Kuhlmann Andreas V., Houel Julien, Brunner Daniel, Ludwig Arne, Reuter Dirk, Wieck Andreas D., Warburton Richard J. (2013), A dark-field microscope for background-free detection of resonance fluorescence from single semiconductor quantum dots operating in a set-and-forget mode, in REVIEW OF SCIENTIFIC INSTRUMENTS
, 84(7), 073905.
Kuhlmann Andreas V., Houel Julien, Ludwig Arne, Greuter Lukas, Reuter Dirk, Wieck Andreas D., Poggio Martino, Warburton Richard J. (2013), Charge noise and spin noise in a semiconductor quantum device, in NATURE PHYSICS
, 9(9), 570-575.
Sapienza Luca, Malein Ralph N. E., Kuklewicz Christopher E., Kremer Peter E., Srinivasan Kartik, Griffiths Andrew, Clarke Edmund, Gong Ming, Warburton Richard J., Gerardot Brian D. (2013), Exciton fine-structure splitting of telecom-wavelength single quantum dots: Statistics and external strain tuning, in PHYSICAL REVIEW B
, 88(15), 155330.
Prechtel Jonathan H., Kuhlmann Andreas V., Houel Julien, Greuter Lukas, Ludwig Arne, Reuter Dirk, Wieck Andreas D., Warburton Richard J. (2013), Frequency-Stabilized Source of Single Photons from a Solid-State Qubit, in PHYSICAL REVIEW X
, 3(4), 041006.
Rakher Matthew T., Warburton Richard J., Treutlein Philipp (2013), Prospects for storage and retrieval of a quantum-dot single photon in an ultracold Rb-87 ensemble, in PHYSICAL REVIEW A
, 88(5), 053834.
Heiss M., Fontana Y., Gustafsson A., Wuest G., Magen C., O'Regan D. D., Luo J. W., Ketterer B., Conesa-Boj S., Kuhlmann A. V., Houel J., Russo-Averchi E., Morante J. R., Cantoni M., Marzari N., Arbiol J., Zunger A., Warburton R. J., Fontcuberta i Morral A. (2013), Self-assembled quantum dots in a nanowire system for quantum photonics, in NATURE MATERIALS
, 12(5), 439-444.
Warburton RJ (2013), Single spins in self-assembled quantum dots, in Nature Materials
, 12, 483-493.
Tanner MG, San Emeterio Alvarez L, Jiang W, Warburton RJ, Barber ZH, Hadfield RH (2012), A superconducting nanowire single photon detector on lithium niobate, in Nanotechnology
, 23, 505201.
Prechtel JH, Dalgarno PA, Hadfield RH, McFarlane J, Badolato A, Petroff PM, Warburton RJ (2012), Fast electro-optics of a single self-assembled quantum dot in a charge-tunable device, in JOURNAL OF APPLIED PHYSICS
, 111(4), 043112-043112.
Hunger D, Deutsch C, Barbour RJ, Warburton RJ, Reichel J (2012), Laser micro-fabrication of concave, low-roughness features in silica, in AIP ADVANCES
, 2(1), 012119-012119.
Houel J, Kuhlmann AV, Greuter L, Xue F, Poggio M, Gerardot BD, Dalgarno PA, Badolato A, Petroff PM, Ludwig A, Reuter D, Wieck AD, Warburton RJ (2012), Probing Single-Charge Fluctuations at a GaAs/AlAs Interface Using Laser Spectroscopy on a Nearby InGaAs Quantum Dot, in PHYSICAL REVIEW LETTERS
, 108(10), 107401-107401.
Barbour RJ, Dalgarno PA, Curran A, Nowak KM, Baker HJ, Hall DR, Stoltz NG, Petroff PM, Warburton RJ (2011), A tunable microcavity, in JOURNAL OF APPLIED PHYSICS
, 110(5), 053107-053107.
Kloeffel C, Dalgarno PA, Urbaszek B, Gerardot BD, Brunner D, Petroff PM, Loss D, Warburton RJ (2011), Controlling the Interaction of Electron and Nuclear Spins in a Tunnel-Coupled Quantum Dot, in PHYSICAL REVIEW LETTERS
, 106(4), 046802-046802.
Gerardot BD, Barbour RJ, Brunner D, Dalgarno PA, Badolato A, Stoltz N, Petroff PM, Houel J, Warburton RJ (2011), Laser spectroscopy of individual quantum dots charged with a single hole, in APPLIED PHYSICS LETTERS
, 99(24), 243112-243112.
Simon CM, Belhadj T, Chatel B, Amand T, Renucci P, Lemaitre A, Krebs O, Dalgarno PA, Warburton RJ, Marie X, Urbaszek B (2011), Robust Quantum Dot Exciton Generation via Adiabatic Passage with Frequency-Swept Optical Pulses, in PHYSICAL REVIEW LETTERS
, 106(16), 166801-166801.
Semiconductor heterostructures have uniquely attractive properties for both electronics and opto-electronics applications. Semiconductors underpin information processing: electronic signals are manipulated at GHz frequencies with semiconductor devices and signals are transmitted over large distances via optical fibres using semiconductor lasers and detectors. It is however presently unclear if these material advantages can be exploited in the creation of a new type of device manipulating coherent quantum states. Radical proposals exist in the areas of communication, metrology, imaging and information processing. The stumbling block to the successful application of these ideas in a semiconductor is the rapid loss of coherence via dephasing. A single, localized spin is potentially coherent even in a semiconductor as the spin interacts only indirectly with the main source of dephasing, the phonons. Given the rather short coherence times in semiconductors, optical methods of spin manipulation are very attractive, and the optical interaction can be amplified and exploited in rich and varied ways with a miniaturized optical cavity, a microcavity. This project aims to create a coherent single quantum state based on a single hole spin, and its integration into a fully-tunable microcavity.Coherent quantum dot spin (project A) A semiconductor heavy hole spin is constructed from a p-like Bloch state which conveniently goes to zero at the location of the nucleus, eliminating the contact part of the hyperfine interaction. The dipole part of the interaction still remains but has an Ising-like form. The theoretical prediction is that a highly localized single hole spin can be coherent: on the one hand, quantization suppresses the dephasing via the phonons; on the other hand, an in-plane magnetic field suppresses the dephasing via the fluctuating nuclear spins. Experimentally however, very little is known about the hole spin coherence. A programme of experiments will be launched, exploring the single hole spin coherence with a quantum interference effect - coherent population trapping (CPT) and stimulated Raman adiabatic passage (STIRAP) - and with spin resonance. A coherent hole spin will be engineered by tailoring both the quantum dots and the external parameters.A fully tunable microcavity (project B) Existing micro-cavities do not allow in situ spatial tuning of the nanostructure to the cavity anti-node, have limited in situ spectral tuning, and are difficult to integrate with electronics. A generic microcavity platform, a miniaturized Fabry-Perot cavity, will be developed offering complete spatial and spectral tuning, high Q-factor, low volume and compatibility with a range of nanostructures (quantum dots, semiconductor nanostructures, colour centres in diamond). The applicant, Prof. Dr. Richard J. Warburton (RJW), has recently been elected Ordinarius Professor of Condensed Matter Physics in the Physics Department at the University of Basel. RJW moves to Basel from Heriot-Watt University, Edinburgh, UK where he founded the Nano-Optics Group in 2000, becoming full Professor in 2005. RJW's expertise is in the optics of semiconductors covering a wide range of frequencies, material systems and applications. RJW's Nano-optics group in Edinburgh has focused primarily on the physics of quantum dots yielding high profile publications: 4 Nature, 1 Science, 1 Nature Physics, 1 Nature Photonics and 8 Physical Review Letters. RJW has been invited to over 30 international conferences in the past 7 years including the major semiconductor conferences (ICPS 2002, QD 2004, QD 2008, MSS 2009), the major US meetings (APS March Meeting 2000, 2005 and 2009; MRS Fall Meeting 2002, 2007 and 2009; Photonics West 2008) and also meetings on quantum information (eg keynote speaker at Quantum Information Science and Quantum Decoherence, Leiden 2008). RJW will give a plenary lecture at ICPS 2010 and a keynote talk at QD 2010. RJW's work in the UK has been funded by EPSRC, grants totaling £4.3M all awarded in a very competitive environment. RJW was elected to a Fellowship of the Royal Society of Edinburgh in 2009. RJW studied originally in Oxford (MA and DPhil degrees), and worked at the Center for NanoScience at Ludwig-Maximilians-University, Munich, as von Humboldt Fellow (1993-94), Marie-Curie Fellow (1994-96) and Assistant Professor (1996-99).