445. WE-Heraeus-Seminar: Quantum Measurement, Metrology, and Limits in Solid State Devices

Quantum Measurement, Metrology, and Limits in Solid State Devices

So, 01.11.2009 18:30  –   Do, 05.11.2009 13:00
G. Schön, U Karlsruhe; A. Zorin, PTB Braunschweig
Physikzentrum Bad Honnef
Hauptstr. 5, 53604 Bad Honnef, Germany

Wilhelm and Else Heraeus-Foundation
Prof. Dr. Gerd Schön,


Ten years after the first demonstration of quantum coherent oscillations in solid state devices it has become apparent that the original goal, a solid state quantum computer, remains elusive. On the other hand, the world-wide activities stimulated by this quest have substantially advanced our understanding of quantum mechanics and the development of the related technologies. Examples are the progress with quantum measurement techniques as well as the use of quantum information systems as sensors and etalons for metrological applications.
Solid state quantum systems usually cannot compete in quality with that of atomic or optical systems but provide access to complementary properties. The direct coupling of solid state qubits to electric circuits allows precision measurements of currents, magnetic fields, and electric charges. It is expected that the enhanced precision will lead to a redefinition of the SI units based on fundamental constants as defined by quantum mechanical effects. Solid state quantum information devices are also sensitive probes for microscopic material properties, such as the 1/f noise.
Many of the concepts playing a role in solid state quantum information systems are known from quantum optics and atomic physics. But, due to advanced fabrication and control techniques, solid state devices are more flexible and operate in new parameter regimes. E.g., in circuit QED systems concepts of quantum electrodynamics, i.e., of atoms coupling to a radiation field, are reproduced and extended with solid state qubits coupled to electric resonators. Superconducting quantum circuits of high quality allow controlling single photons in the micrometer regime.
An example for the progress in understanding of quantum mechanics is the quantum measurement process. Today quantum non-demolishing measurements can be performed with near 100% fidelity in (close to) single-shot measurements. The demonstrated precision reaches close to the quantum limit. Josephson junctions with their high coherence and controlled anharmonicities are ideal systems for bifurcation amplifiers and measurement devices.
The spectrum of question indicated above serves as a excellent basis for a most interesting scientific meeting and school. It is the goal of the Heraeus seminar to bring together leading scientists for an exchange of ideas, and to introduce young physicist into the timely field and let them share the present excitement. For this purpose we invite a number of experts from the relevant fields, which apart from solid state quantum information includes quantum optics and metrology.

The Seminar will include, but is not limited to the following fields:
Quantum electrical metrology
Quantum-limited and QND measurements
Single charge effects
Solid state qubits
Noise spectroscopy
Circuit QED
Parametric effects in superconducting circuits

Invited speakers:

O. Astafiev / Y. Nakamura (NEC): Noise spectroscopy
C.M. Caves (U New Mexico): Quantum metrology
J. Clarke (UC Berkeley): Ultimate sensitivity of SQUIDs
M. Devoret (Yale): Josephson-based parametric amplifiers
D. Esteve (CEA Saclay): Frequency-current conversion in single Cooper pair circuits
D. Haviland (KTH Stockholm): Nonlinear electrodynamics with Josephson Junction Series Arrays
A. Imamoglu (ETH Zürich): Optical manipulation and measurement of spins in quantum dots
F. Khalili (Moscow State U): QND measurements of macroscopic mechanical objects
A. Korotkov (UC Riverside): Non-projective measurement of solid-state qubits
J. Martinis (UC Santa Barbara): Generating arbitrary photon states in superconducting resonators: the quantum digital to analog converter
J. Twamley (Macquarie University): Quantum control and measurement
J. Pekola (Helsinki U of Technology): Hybrid single-electron turnstile
F. Piquemal (LNE, France): Quantum metrology triangle
P. Schmidt (Innsbruck U, PTB): Quantum Logic Spectroscopy and Precision Measurements
K. Schwab (Cornell U): Nano-mechanical systems
A. Shnirman (U Karlsruhe): Noise spectroscopy, 1/f noise
A. Tzalenchuk (NPL, UK): Quantum measurements and metrology
A. Ustinov (U Karlsruhe): Towards ballistic devices: charge and flux solitons
A. Wallraff (ETH Zürich): Photons, Qubits and Computers - A Quantum Mechanics Lab on a Chip
F. K. Wilhelm (U Waterloo): Josephson bifurcation amplifier
M. Wulf (PTB Braunschweig): Error correction in electron-counting experiments
R. Gross (WMI TU München) : Cross-correlation detection of weak microwave signals: vacuum fluctuations and variance of nontrivial propagating signals