Suppressed dissipation of a quantum emitter coupled to surface plasmon polaritons

Abstract

Enabling the confinement of light to a scale far below the one of conventional optics, surface plasmon polaritons (SPPs) induced by an electromagnetic field in a metal-dielectric interface supply an ideal system to explore strong quantized light-matter coupling. The fast matter-SPP population exchange reported in previous works makes it a candidate for spin manipulation, but such reversible dynamics asymptotically vanishes accompanying the quantum matter relaxing completely to its ground state. Here, we study the exact dissipative dynamics of a quantum emitter (QE) coupled to SPPs. It is interesting to find that, qualitatively different from conventional findings, the QE can be partially stabilized in its excited state even in the presence of the lossy metal. Our analysis reveals that it is the formation of a QE-SPP bound state which results in such suppressed dissipation. Enriching the decoherence dynamics of the QE in the lossy medium, our result is helpful to understand QE-SPP interactions and apply plasmonic nanostructures in quantum devices.Introduction.-Surface plasmon polaritons (SPPs) triggered by an electromagnetic field along a metaldielectric interface supply an ideal platform to explore strong quantized light-matter coupling [1][2][3][4][5]. Such couplings were achieved conventionally in cavity and circuit QED by boosting the interaction times, but at the price of a limited optical bandwidth and diffraction size [6][7][8][9]. Realizing strong confinement of light below the diffraction limit, SPPs have inspired great interest in studying subwavelength optics and quantum plasmonics [10,11]. Much effort has been made to realize strong or even ultrastrong coupling between SPPs and a quantum emitter (QE) made of, for example, quantum dots, quantum defects, or nitrogen vacancy centers [12][13][14]. It makes surface plasmonics a promising platform to design quantum devices [15][16][17][18], where the coupling is a prerequisite. However, the dissipation induced by the lossy metal to the QE severely limits its practical use.Owing to the strong spatial confinement of the radiation field of the QE near the metal-dielectric interface, the decoherence dynamics of the QE exhibits significant reversibility. Based on the dyadic Green's tensor formalism, the quantization of an electromagnetic field in a lossy medium was developed in Ref. [19], from which the quantized interactions between QE and SPPs can be studied. It was found that the spectral density of the SPPs approaches a Lorentzian form when the QEinterface distance is much smaller than the typical wavelength of the SPPs [20]. In this regime, the decoherence of the QE caused by the SPPs can be approximately stimulated by a Markovian one with QE coupled to an artificial pseudo damping cavity mode [21][22][23][24][25][26][27][28]. Thus one can use the well-developed tools in cavity QED to study QE-SPP interactions. Based on this method, the interplay between quenching and strong coupling of QE near a metal nanoparticle [26] and the dissipative dynamics of QE ne...

Quantum metrology in local dissipative environments

“…Our result is confirmable in the circuit QED platform [61], where the bound state has been observed in the photonic band-gapped environment. Note that our result is extendable to other spectral densities [55,59], where the formation mechanism of the bound state is the same. Although only the dissipative quantum metrology based on the Ramsey interferometer is studied, the revealed mechanism is applicable to both the magnetic field sensing [30] and the Mach-Zehnder interferometer [62], where the dissipation of the quantized light has the same dynamical equation as equation (5) [63].…”

“…It can be realized by fabricating the spatial confinement of the radiation field such that the dispersion relation of the atomic radiation field is efficiently changed. Such spatial fabrication includes the three-dimensional periodic structure in the photonic crystal, which results in the band-gapped dispersion relation [56,57], and the twodimensional quantum surface plasmonics, which results in the strongly surface-confined propagation of the radiation field [58,59]. All these exotic environmental characteristics in turn would make the properties of the atomic dissipation changeable.…”

How nonlocal damping reduces plasmon-enhanced fluorescence in ultranarrow gaps

“…Departing from this description is more common when one is interested in the dynamics of quantum emitter coupling with plasmonic nanostructures [35][36][37][38]. Nevertheless, the tremendous recent advances in cavity minimization have now led to a necessity for the inclusion of nonclassical * ctse@fotonik.dtu.dk effects such as nonlocal screening and electron spill out [39][40][41][42] in the modeling of the plasmonic nanostructures [43,44].…”

Influence of Surface Roughness on Strong Light-Matter Interaction of a Quantum Emitter-Metallic Nanoparticle System

“…First, without making Markovian approximation, the LSES and FFDS are valid in both the weak and the strong coupling regime. Second, we can obtain the reversible dynamics of QE in the strong coupling regime 71 – 73 through the Fourier transformation of LSES C e ( ω ). Finally, our method can also be extended to multiple QEs system to find out the underlying cooperative effect under strong light-matter interaction.…”