Superluminal group velocity in a birefringent crystal
نویسندگان
چکیده
منابع مشابه
Group-velocity-matched three-wave mixing in birefringent crystals.
It is shown that the combination of pulse-front slant, kappa -vector tilt, and crystal birefringence often permits exact matching of both phase and group velocities for three-wave mixing in birefringent crystals. This exact match makes possible more-efficient mixing of short light pulses, and it permits efficient mixing of chirped or broadband light. I analyze this process and present examples.
متن کاملSuperluminal Signal Velocity
It recently has been demonstrated that signals conveyed by evanescent modes can travel faster than light. In this report some special features of signals are introduced and investigated, for instance the fundamental property that signals are frequency band limited. Evanescent modes are characterized by extraordinary properties: Their energy is negative, they are not directly measurable, and the...
متن کاملDirect measurement of superluminal group velocity and signal velocity in an optical fiber.
We present an easy way of observing superluminal group velocities using a birefringent optical fiber and other standard devices. In the theoretical analysis, we show that the optical properties of the setup can be described using the notion of "weak value." The experiment shows that the group velocity can indeed exceed c in the fiber; and we report the first direct observation of the so-called ...
متن کاملPropagation of a squeezed optical field in a medium with superluminal group velocity.
We investigated the propagation of a squeezed optical field, generated via the polarization self-rotation effect, with a sinusoidally modulated degree of squeezing through an atomic medium with anomalous dispersion. We observed the advancement of the signal propagating through a resonant Rb vapor compared to the reference signal, propagating in air. The measured advancement time grew linearly w...
متن کاملSuperluminal Velocity To Time Machines ?
Various experiments have shown superluminal group and signal velocities recently. Experiments were essentials carried out with microwave tunnelling [1], with frustrated total internal reflection [2], and with gain-assisted anomalous dispersion [3]. According to text books a superluminal signal velocity violates Einstein causality implying that cause and effect can be changed and time machines k...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review A
سال: 2008
ISSN: 1050-2947,1094-1622
DOI: 10.1103/physreva.77.023808