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arXiv · 1009.2996

Zitterbewegung of optical pulses in nonlinear frequency conversion

Stefano Longhi
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Abstract

Pulse walk-off in the process of sum frequency generation in a nonlinear $\chi^{(2)}$ crystal is shown to be responsible for pulse jittering which is reminiscent to the Zitterbewegung (trembling motion) of a relativistic freely moving Dirac particle. An analytical expression for the pulse center of mass trajectory is derived in the no-pump-depletion limit, and numerical examples of Zitterbewegung are presented for sum frequency generation in periodically-poled lithium niobate. The proposed quantum-optical analogy indicates that frequency conversion in nonlinear optics could provide an experimentally accessible simulator of the Dirac equation.

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Stefano Longhi. 2010-09-15. Zitterbewegung of optical pulses in nonlinear frequency conversion. https://doi.org/10.1088/0953-4075/43/20/205402

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