Lecture

Quantum Metrology: Superconducting Electronics & Qubits

Graph Chat

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Description

This lecture covers the fundamentals of quantum metrology, focusing on superconducting electronics. It delves into the theory of superconductivity, Josephson junctions, SQUIDs, and various types of superconducting detectors. The discussion extends to the development of nanowire-based electronics, including nTrons, yTrons, and hTrons, and their applications in quantum computing. The lecture also explores the challenges and advancements in superconducting single-photon detectors, emphasizing their superior performance in quantum information applications. Additionally, it delves into the principles of qubits, including the Cooper Pair Box and transmons, highlighting their significance in quantum computing. The lecture concludes with insights into quantum supremacy and the fabrication and measurements of transmons.

Official source

Ontological neighbourhood

Physics

Condensed matter physics: Phase transitions

Theoretical computer science

Theory of computation: Quantum computing

Related concepts (32)

Superconducting quantum computing

Superconducting quantum computing is a branch of solid state quantum computing that implements superconducting electronic circuits using superconducting qubits as artificial atoms, or quantum dots. For superconducting qubits, the two logic states are the ground state and the excited state, denoted respectively. Research in superconducting quantum computing is conducted by companies such as Google, IBM, IMEC, BBN Technologies, Rigetti, and Intel. Many recently developed QPUs (quantum processing units, or quantum chips) utilize superconducting architecture.

Quantum computing

A quantum computer is a computer that exploits quantum mechanical phenomena. At small scales, physical matter exhibits properties of both particles and waves, and quantum computing leverages this behavior, specifically quantum superposition and entanglement, using specialized hardware that supports the preparation and manipulation of quantum states. Classical physics cannot explain the operation of these quantum devices, and a scalable quantum computer could perform some calculations exponentially faster than any modern "classical" computer.

Charge qubit

In quantum computing, a charge qubit (also known as Cooper-pair box) is a qubit whose basis states are charge states (i.e. states which represent the presence or absence of excess Cooper pairs in the island). In superconducting quantum computing, a charge qubit is formed by a tiny superconducting island coupled by a Josephson junction (or practically, superconducting tunnel junction) to a superconducting reservoir (see figure). The state of the qubit is determined by the number of Cooper pairs that have tunneled across the junction.

Cryogenic particle detector

Cryogenic particle detectors operate at very low temperature, typically only a few degrees above absolute zero. These sensors interact with an energetic elementary particle (such as a photon) and deliver a signal that can be related to the type of particle and the nature of the interaction. While many types of particle detectors might be operated with improved performance at cryogenic temperatures, this term generally refers to types that take advantage of special effects or properties occurring only at low temperature.

Flux qubit

In quantum computing, more specifically in superconducting quantum computing, flux qubits (also known as persistent current qubits) are micrometer sized loops of superconducting metal that is interrupted by a number of Josephson junctions. These devices function as quantum bits. The flux qubit was first proposed by Terry P. Orlando et al. at MIT in 1999 and fabricated shortly thereafter. During fabrication, the Josephson junction parameters are engineered so that a persistent current will flow continuously when an external magnetic flux is applied.

Related lectures (64)

Quantum and Nanocomputing

Covers the birth of quantum mechanics, Schrödinger's equations, superconductivity, Josephson effect, and the theory of superconductivity.

Germanium Quantum Technology

Delves into the use of germanium in quantum computing, emphasizing hole-based quantum systems and materials advancements.

Trapped Ions: Quantum Gates

Covers the fundamentals of trapped ions in quantum information and the importance of geometric phases in quantum optics.

Quantum Computing Basics

Covers the basics of quantum computing, focusing on superconducting qubits, scaling challenges, and potential applications.

Superconducting Qubits: Circuit QED Technology