Abstract
In various leading-edge ultracold atom experiments in fields such as quantum simulation, quantum computing, and quantum precision measurement, precise and fast control of the magnetic field is important and a current source with a low noise level and high control bandwidth is required. Conventional commercial current sources, even the expensive ones, may not meet the requirements. Here, we present a battery-powered current source (BPCS) solution that has a maximum output of 100 A with a root-mean-square noise of about only 0.35 mA (integrated from 1 Hz to 3 MHz) and a control bandwidth of about 10 kHz. The large output current is sourced from a lead-acid battery, a fluxgate current sensor is used to detect the output current, and fast feedback regulation is done by using an insulated-gate bipolar transistor under the control of an analog proportional-integral controller. The battery power method eliminates the switching noise. A prepulse method is applied to shorten the settling time when the current steps down from a high level to a low level that is close to zero. These features make the BPCS a suitable analog-controlled floating current source for cold-atom experiments such as the preparation of a single 2D quantum gas and optical lattice atomic clocks.
Highlights
Cold atoms are an important research medium for the research fields of quantum simulation1 and quantum precision measurement
We present a battery-powered current source (BPCS) solution that has a maximum output of 100 A with a root-mean-square noise of about only 0.35 mA and a control bandwidth of about 10 kHz
The large output current is sourced from a lead-acid battery, a fluxgate current sensor is used to detect the output current, and fast feedback regulation is done by using an insulated-gate bipolar transistor under the control of an analog proportional-integral controller
Summary
Cold atoms are an important research medium for the research fields of quantum simulation and quantum precision measurement. An analog-controlled current source that can produce high current in the order of hundreds of amps with ultra-low noise and high bandwidth is needed in many cold-atom experiments. Conventional power supplies are generally based on switching technology and deliver large switching noise, which can be larger than 10 mA when the maximum output current reaches 100 A. The goal is to produce a voltage-controlled current source that can generate a maximum current of 100 A, with integrated noise and interference better than 1 mA (rms) (1 Hz–3 MHz) and a control bandwidth around 10 kHz. The high current is sourced from a lead-acid battery, a fluxgate current sensor is used to detect the output current, and fast feedback regulation is done by using an insulated-gate bipolar transistor (IGBT) under the control of an analog proportional-integral (PI) controller.. We show in detail the noise performance of the BPCS and compare it with a commercial power supply
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
