COOKIES: By using this website you agree that we can place Google Analytics Cookies on your device for performance monitoring. |

University of Cambridge > Talks.cam > Semiconductor Physics Group Seminars > Probing the limits of gate-based charge sensing

## Probing the limits of gate-based charge sensingAdd to your list(s) Download to your calendar using vCal - Dr. M. Fernando Gonzalez Zalba, Hitachi Cambridge Laboratory
- Monday 20 October 2014, 14:15-15:15
- Mott Seminar Room, Cavendish Laboratory, Department of Physics.
If you have a question about this talk, please contact Teri Bartlett. Quantum computation requires a qubit-specific measurement capability to readout the final state of individual qubits. In the promising solid-state approaches based on superconducting and semiconducting nano-devices experiments are increasing in complexity and it becomes important to simplify the circuit layout and decrease the number of components. One of the components of solid-state quantum computers are the qubit readout electrometers. They are made redundant by the introduction of in-situ gate sensors based on a resonant readout. This technique couples the gate to a resonant circuit and probes the qubit’s radio-frequency polarisability. Here, we investigate the ultimate performance of such resonant readout schemes and the noise sources that limit their operation. We find a charge sensitivity of 37 ue/\sqrt{Hz}, the best value reported for this technique, using the example of a gate-sensor strongly coupled to a double quantum dot at the corner states of a silicon nanowire transistor. We model the charge and phase noise by solving the dynamical master equation of the fast-driven electronic transitions and determine the limits of charge and phase sensitivity of resonant readout. We find comparable performance to standard charge sensors and our model predicts limits of order ne/\sqrt{Hz} and urad/\sqrt{Hz}. We discuss the experimental factors limiting gate detection and highlight ways to optimise its sensitivity. In total, resonant gate-based detection has advantages over external electrometers not only in terms of reduced number of circuit elements, but also in terms of absolute charge sensitivity. This talk is part of the Semiconductor Physics Group Seminars series. ## This talk is included in these lists:- All Cavendish Laboratory Seminars
- All Talks (aka the CURE list)
- Centre for Health Leadership and Enterprise
- Featured lists
- ME Seminar
- Mott Seminar Room, Cavendish Laboratory, Department of Physics
- Neurons, Fake News, DNA and your iPhone: The Mathematics of Information
- School of Physical Sciences
- Semiconductor Physics Group Seminars
- Thin Film Magnetic Talks
Note that ex-directory lists are not shown. |
## Other listsEngineering Department Computing Seminars Innovation Forum Applied and Computational Analysis Graduate Seminar CUUEG The Real Me: Cambridge University Global Health Student Initiative## Other talksDeveloping joint research between a UK university and and INGO on disability and education: opportunities and challenges Tracking neurobiological factors of language developmental difficulties CANCELLED DUE TO STRIKE ACTION Recent advances in understanding climate, glacier and river dynamics in high mountain Asia Intrinsically Motivating Teachers;STIR's use of Data Driven Insight to Iterate, Pivot and (where necessary) Fail Fast Measuring interacting electrons in low dimensional systems: spin-charge separation and 'replicas & tbd 'Alas, poor Yorick!': Laurence Sterne's "A Sentimental Journey" after 250 years' |