Article

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

University of Bergamo, Bérgamo, Lombardy, Italy
Physical Review E (Impact Factor: 2.29). 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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Available from: Erasmo Recami
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    • "Even more strikingly, Recami [24] notes that " at least four different experimental sectors of physics seem to indicate the actual existence of Superluminal motions " , two of which have been confirmed both theoretically and experimentally [23]. In particular, various experiments [14] [17] [20] [29] (cf. [18]) have confirmed the quantum-theoretical prediction [1] that the total time taken for a photon to 'tunnel' through an opaque barrier is independent of tunnel width, whence group velocities are necessarily superluminal for wide enough barriers. "
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    • "Such a prediction has been verified a second time, taking advantage of the circumstance that quite interesting evanescence regions can be constructed in the most varied manners, like by means of different photonic bandgap materials or gratings (it is possible to use multilayer dielectric mirrors, or semiconductors, to photonic crystals… ). And, indeed, a very recent confirmation came, as already mentioned, from an experiment having recourse to two gratings in an optical fiber [81]. We cannot skip a further, indeed delicate, topic, since the last experimental contribution to it [77], aroused large interest. "
    Dataset: JSTQE

    Full-text · Dataset · Jul 2013
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    • "Such a prediction has been verified a second time, taking advantage of the circumstance that quite interesting evanescence regions can be constructed in the most varied manners, like by means of different photonic band-gap materials or gratings (it being possible to use from multilayer dielectric mirrors, or semiconductors, to photonic crystals...). And indeed a very recent confirmation came —as already mentioned— from an experiment having recourse to two gratings in an optical fiber.[25] We cannot skip a further, indeed delicate, topic, since the last experimental contribution to it[23] aroused large interest. "
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