Measurement of superluminal optical tunneling times in double-barrier photonic band gaps.

Istituto Nazionale per la Fisica della Materia, Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy.
Physical Review E (Impact Factor: 2.33). 05/2002; 65(4 Pt 2B):046610. DOI: 10.1103/PhysRevE.65.046610
Source: PubMed

ABSTRACT Tunneling of optical pulses at 1.5 microm wavelength through double-barrier periodic fiber Bragg gratings is experimentally investigated in this paper. Tunneling time measurements as a function of the barrier distance show that, far from resonances of the structure, the transit time is paradoxically short--implying superluminal propagation--and almost independent of the barrier distance. This result is in agreement with theoretical predictions based on phase-time analysis and provides, in the optical context, an experimental evidence of the analogous phenomenon in quantum mechanics of nonresonant superluminal tunneling of particles across two successive potential barriers.

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