Microcontroller-based locking in optics experiments.

Optics experiments critically require the stable and accurate locking of relative phases between light beams or the stabilization of Fabry-Perot cavity lengths. Here, we present a simple and inexpensive technique based on a stand-alone microcontroller unit to perform such tasks. Easily programmed in C language, this reconfigurable digital locking system also enables automatic relocking and sequential functioning. Different algorithms are detailed and applied to fringe locking and to low- and high-finesse optical cavity stabilization, without the need of external modulations or error signals. This technique can readily replace a number of analog locking systems advantageously in a variety of optical experiments.

[1]  Julien Laurat,et al.  High-fidelity single-photon source based on a Type II optical parametric oscillator. , 2012, Optics letters.

[2]  Valerio Biancalana,et al.  Long-term drift laser frequency stabilization using purely optical reference. , 2002 .

[3]  Jesse E. Simsarian,et al.  A computer-based digital feedback control of frequency drift of multiple lasers , 1998 .

[4]  A. White,et al.  Frequency stabilization of gas lasers , 1965 .

[5]  Experimental demonstration of frequency-degenerate bright EPR beams with a self-phase-locked OPO. , 2008, Optics express.

[6]  C. Fabre,et al.  Quantum state engineering of light with continuous-wave optical parametric oscillators. , 2014, Journal of visualized experiments : JoVE.

[7]  Vitus Händchen,et al.  Stable control of 10 dB two-mode squeezed vacuum states of light. , 2013, Optics express.

[8]  Timothy C. Ralph,et al.  A Guide to Experiments in Quantum Optics , 1998 .

[10]  Erkki Ikonen,et al.  A digital control system for the iodine stabilized He–Ne laser , 1998 .

[11]  John L. Hall,et al.  Laser phase and frequency stabilization using an optical resonator , 1983 .

[12]  Ying Li,et al.  Precise Frequency-Drift Measurement of Extended-Cavity Diode Laser Stabilized with Scanning Transfer Cavity , 2005 .

[13]  Julien Laurat,et al.  Remote creation of hybrid entanglement between particle-like and wave-like optical qubits , 2013, Nature Photonics.

[14]  Wolfgang Lange,et al.  Fast scanning cavity offset lock for laser frequency drift stabilization. , 2010, The Review of scientific instruments.

[15]  B C Buchler,et al.  A scalable, self-analyzing digital locking system for use on quantum optics experiments. , 2011, The Review of scientific instruments.

[16]  D E McClelland,et al.  Frequency locking a laser to an optical cavity by use of spatial mode interference. , 1999, Optics letters.

[17]  Olivier Morin,et al.  Experimentally accessing the optimal temporal mode of traveling quantum light states. , 2013, Physical review letters.

[18]  C. Fabre,et al.  Experimental demonstration of frequency-degenerate bright EPR beams with a self-phase-locked optical parametric oscillator , 2008 .

[19]  Hidehiro Yonezawa,et al.  Observation of -9 dB quadrature squeezing with improvement of phase stability in homodyne measurement. , 2007, Optics express.