Demonstration of Quadrature-Squeezed Surface Plasmons in a Gold Waveguide

Abstract

We report on the efficient generation, propagation, and reemission of squeezed long-range surface-plasmon polaritons in a gold waveguide. Squeezed light is used to excite the nonclassical surface-plasmon polaritons, and the reemitted quantum state is fully characterized by complete quantum tomographic reconstruction of the density matrix. We find that the plasmon-assisted transmission of nonclassical light in metallic waveguides can be described by a beam splitter relation. This result is explained theoretically.

Fluctuation properties of phonons generated by ultrafast optical excitation of a quantum dot

“…While coherent states are the most classical states, squeezed states provide prominent examples for nonclassical states. In this context the fluctuation properties of photons have been widely studied [1][2][3], but recently also the fluctuation properties of other boson systems attracted a lot of attention, e.g., atomic Bose-Einstein condensates [4], surface plasmons [5], magnons [6], or phonons [7][8][9][10][11][12][13]. The fluctuation properties of phonons were studied in many different systems including metals and semimetals [7][8][9], perovskite materials [10][11][12], semiconductors [7] as well as high-T C superconductors [13].…”

Expressing complementarity and the x – p commutation relation through further quantum inequalities

“…p q , q q and r q are given in equations (10) and (11). The quartic equation f 4,q (λ) = 0 in (A.2) can be solved by reducing it to either a biquadratic equation in a special case or, in general, to a cubic one.…”

“…To see whether this question could receive some clarification from the further quantum conditions to be treated here seems also physically interesting. For an additional appreciation of the physical relevance of squeezing, we shall just mention that, very recently, the latter has also been demonstrated experimentally for surface-plasmon polaritons (namely, combined electron oscillations and electromagnetic waves propagating along the interface between a conductor and a dielectric medium) in a gold waveguide [11].…”

Preservation of photon indistinguishability after transmission through surface-plasmon-polariton waveguide

“…Although the preservation of quantum states of light (i.e., entangled photon pairs) have been demonstrated, these experimental results do not exhibit all of the aspects of optical quantum state preservation via the photon-plasmon-photon mode conversions. On the other hand, recently, plasmon-assisted transmission of nonclassical light has been characterized [12,13]. Then, only static scattering mechanisms contributed to the decoherence of the optical quantum state [12].…”