A superconducting quantum interference device (SQUID) is an extremely sensitive magnetic field detector. Microstrip SQUIDs can amplify weak radio frequency (RF) signals, a capability that makes them attractive as a potential alternative to the cryogenic semiconductor-based RF amplifiers that are available commercially, but at a cost of approximately $6,000 each. The challenge of using microstrip SQUIDs has been that they are static sensitive and can be overwhelmed by external noise. By tweaking microstrip SQUID design to achieve the quantum noise limit, and by packaging the technology into a more practical configuration, our team is working to reduce the cost of the SQUID approach by an order of magnitude. We also are working toward a much higher performance amplifier, with voltage noise reduced ten fold.
In the course of our work, we expect to fabricate “user-friendly” SQUIDs – packaging the RF filtering, RF-SQUID, and amplification together – such that a non-specialist could easily run the amplifier with the ease of running a conventional semiconductor amplifier. In addition to producing a practical, high-performance and economical amplifier, we believe that our work will facilitate multiple new quantum readout applications, as well as interesting fundamental physics.
Carbon Nanotube Monolayer Josephson Junction Superconducting Qubit
Carbon nanotubes (CNTs) are a promising material for use in Josephson-Junctions (JJs) given their unique properties, such as high electrical conductivity, pristine surface, inherent nanoscale dimension, and silicon-compatible processing
June 1, 2017
Folk Understanding of Quantum Physics
Summary It is often said that quantum concepts are counterintuitive. However, quantum concepts may not be equally counterintuitive to people from all cultural backgrounds. As cultural psychologists have discovered, culture fundamentally shapes the way people make sense of the world. In particular, the last few decades of research have documented cultural differences in appreciation of […]
March 24, 2021
Quantum State Tomography with Machine Learning
Summary An important challenge in building a quantum computer is quantifying the level of control obtained in the preparation of a quantum state. The state of a quantum device is characterized from experimental measurements, using a procedure known as tomography. Exact tomography requires a vast amount of computer resources, making it prohibitive for quantum […]
June 6, 2018
Ultrafast Dynamical Studies of Valley-Based Qubits
Summary As monolayers, transition metal dichalcogenides (TMDCs) – such as tungsten diselenide (WSe2) – become direct-bandgap semiconductors capable of emitting light. Compared to conventional direct-bandgap semiconductors, such as III-V semiconductors like GaAs, excitons (quasiparticles made of an electron hole bound with an electron) and single-layer TMDCs (SL-TMDCs) have much stronger binding energy. Excitons and […]
June 29, 2018