High-speed pulsing circuit for continuous wave laser beams

Abstract Tunable continuous wave (CW) lasers produce the highest optical resolution for pumping and probing atomic and molecular transitions. These lasers adopt sophisticated electronic control of optical components within the cavity to set the wavelength and ensure a narrow bandwidth. The low-cost circuit described here gates a CW laser beam on and off for high resolution timing experiments, using an electro-optic modulator that acts as a switchable waveplate between linear polarizers. The switch can operate at rates of up to 100 kHz with a minimum pulse width of 650 ns, or it can be configured to deliver laser pulses with widths <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mtext>⩾</mml:mtext> </mml:mrow> </mml:math> 35 ns at lower rates. Multiple laser pulses of equal or non-equal widths can also be delivered within each repetition cycle.