GS200 DC Voltage Generator

The GS200 is a low-voltage/current DC current source with high accuracy, stability, and resolution. Thanks to its excellent traceability, stability, and 5½-digit resolution, the GS200 generates the extremely quiet DC voltage and current signals required in many applications. In addition, the optional monitoring function turns the GS200 into a voltage and current measuring instrument.

High accuracy, stability, and resolution
Generates extremely quiet DC voltage and current signals
Optional voltage and current monitoring function
Voltage source up to ±32 V and current up to ±200 mA
5½-digit output resolution

General specifications

Voltage source up to ±32 V and current source up to ±200 mA
5½-digit output resolution, 120000 counts
Simple voltage and current monitoring function (optional)
Programmable output up to 10,000 points
Built-in USB mass storage
Channel expansion through synchronized operation

Application

In recent years, integrated electrical circuits using superconducting electrodes have attracted enormous interest in both scientific and industrial environments. These nanometer-scale devices exhibit various quantum behaviors, such as quantized energy levels or quantum entanglement, making them an excellent candidate for the physical implementation of a scalable quantum computer.

The fundamental element of quantum computers is the quantum bit (qubit), which represents a two-level system in analogy to the classical bit. In superconducting circuits, qubits are built from so-called Josephson junctions, which consist of a superconductor-normal metal-superconductor sequence. The nonlinear element of the Josephson junction, integrated into a closed loop (see figure above), is highly sensitive to small changes in the external magnetic field passing through the loop. When the magnetic field is precisely tuned, the quantized energy levels can be smoothly transformed, which is an unavoidable requirement for initializing a quantum computer. We use a nanometer-scale wire in close proximity to the superconducting loop to generate a magnetic field and consequently tune the qubit energies. In our measurement setup, a small current (~10 mA) flowing through this wire, supplied by the precise Yokogawa GS200 DC voltage/current source, generates a magnetic field to initialize our quantum bits.