Related Experiment Video
Updated: Aug 29, 2025
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
14.6K
Bifurcation Oscillator as an Advanced Sensor for Quantum State Control
Dmitrii Pashin1, Marina Bastrakova1,2, Arkady Satanin3,4
1Faculty of Physics, Lobachevsky State University of Nizhny Novgorod, 603950 Nizhny Novgorod, Russia.
Sensors (Basel, Switzerland)
|September 9, 2022
Summary
We developed a new qubit measurement method using a Josephson oscillator. This technique leverages the oscillator
Area of Science:
- Quantum computing and quantum information science.
- Superconducting circuit quantum electrodynamics.
Background:
- Josephson oscillators coupled to superconducting qubits exhibit complex bifurcation behavior.
- The dynamic equilibrium state of the oscillator is sensitive to the qubit's quantum state.
Purpose of the Study:
- To present a novel measurement method for superconducting qubit superposition states.
- To investigate the quantum-mechanical behavior and entanglement dynamics between a bifurcation oscillator and a qubit.
Main Methods:
- Studying the bifurcation behavior of a high-quality (high-Q) Josephson oscillator coupled to a superconducting qubit.
- Analyzing the influence of qubit states on oscillator transition probabilities near the classical separatrix.
- Investigating quantum-mechanical aspects of the bifurcation oscillator and entanglement mechanisms.
Main Results:
- The capture probability into dynamic equilibrium is demonstrably sensitive to qubit states.
- A new measurement method for qubit superposition states is proposed, exploiting this sensitivity.
- Optimal parameters for driving current and oscillator state were identified for high-precision one-qubit gates with minimal back-action.
- A protocol for measuring state populations of entangled qubit-oscillator systems was developed.
Conclusions:
- The proposed measurement method offers a sensitive approach to detecting qubit superposition states.
- Understanding the quantum-mechanical behavior of the bifurcation oscillator is crucial for qubit-oscillator entanglement.
- The findings facilitate the development of precise quantum gates and measurement protocols in superconducting circuits.
Related Concept Videos
01:30Oscillations In An LC Circuit
2.4K
An idealized LC circuit of zero resistance can oscillate without any source of emf by shifting the energy stored in the circuit between the electric and magnetic fields. In such an LC circuit, if the capacitor contains a charge q before the switch is closed, then all the energy of the circuit is initially stored in the electric field of the capacitor. This energy is given by
2.4K
02:45The Quantum-Mechanical Model of an Atom
42.9K
Shortly after de Broglie published his ideas that the electron in a hydrogen atom could be better thought of as being a circular standing wave instead of a particle moving in quantized circular orbits, Erwin Schrödinger extended de Broglie’s work by deriving what is now known as the Schrödinger equation. When Schrödinger applied his equation to hydrogen-like atoms, he was able to reproduce Bohr’s expression for the energy and, thus, the Rydberg formula governing hydrogen spectra.
42.9K
01:22Bipolar Junction Transistor
897
Bipolar Junction Transistors (BJTs) are essential elements in electronic circuits, playing a crucial role in the functionality of amplifiers, memories, and microprocessors. These transistors can be designed as NPN or PNP based on their doping patterns. They consist of three layers: the emitter, base, and collector. The configuration of these layers and their respective doping levels—with N-type or P-type impurities—define the transistor's type and its operational...
897
01:17Open and closed-loop control systems
941
Control systems are foundational elements in automation and engineering. They are broadly categorized into open-loop and closed-loop systems. These classifications hinge on the presence or absence of feedback mechanisms, significantly influencing the system's performance, complexity, and application.
An open-loop control system operates without feedback from the output. It consists of two primary elements: the controller and the controlled process. The controller receives an input signal...
An open-loop control system operates without feedback from the output. It consists of two primary elements: the controller and the controlled process. The controller receives an input signal...
941
01:29Field Effect Transistor
535
Field-effect transistors (FETs) are integral to electronic circuits and distinguished by their three-terminal setup: the gate, drain, and source. These transistors operate as unipolar devices, which utilize either electrons or holes as charge carriers, in contrast to bipolar transistors, which use both types of carriers. The primary function of the FET is to modulate the flow of these carriers from the source to the drain through a channel. The voltage difference between the gate and source...
535
01:27Biasing of Metal-Semiconductor Junctions
325
Biasing metal-semiconductor junctions involves applying a voltage across the junction. Specifically, the metal is connected to a voltage source, while the semiconductor is grounded. This technique is essential for controlling the direction and magnitude of current flow in electronic devices, including diodes, transistors, and photovoltaic cells.
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
325