Near-field interactions between a subwavelength tip and a small-volume photonic-crystal nanocavity

Abstract

The fundamentals of the near-field interaction between a subwavelength metallic tip and a photonic-crystal nanocavity are investigated experimentally and theoretically. It is shown experimentally that the cavity resonance is tuned without any degradation by the presence of the tip and that the reported near-field interaction is strongly related to the field distribution within the nanostructure. Then, in light of a perturbation theory, we show that this interaction is selectively related to the electric field or magnetic field distribution within the cavity, depending on the tip properties. © 2007 The American Physical Society

Extraction of optical Bloch modes in a photonic-crystal waveguide

“…The reconstructed field patterns are an approximation of the Bloch modes propagating in the system and moreover, they are not necessarily orthogonal because of quasi-interference. Although the effect of the tip is far from straightforward ( [5,20,21]), we anticipate that the comparison between calculated modes of an optical system and reconstructed modes could lead to methods to deduce the response function of a near-field tip. Next, we demonstrate the power of the reconstruction algorithm by studying the transverse behavior of TE-like mode (A) versus wavevector.…”

Subwavelength imaging of light confinement in high-Q/small-V photonic crystal nanocavity

“…However, only low-Q cavities have been studied so far and the very first attempts at probing small volume cavities have shown that the near-field probes ͓SNOM probes in Ref. 12 and atomic force microscopy ͑AFM͒ probes in Refs. 13 and 14͔ strongly alter-or even completely disrupt in the case of AFM probes-the light confinement mechanism inside the cavity.…”

“…12 12,13,15 and the classical SNOM collection-scanning mode. [8][9][10][11] The differences between these two imaging methods are discussed in light of the recorded images by comparing them with three-dimensional ͑3D͒ calculations of the cavity mode.…”

“…Consequently, the near-field probe used here operates in a perturbation regime weak enough to avoid a drastic alteration of the light confinement inside the cavity. 12,20 For SNOM measurements, we then develop an experimental setup allowing the simultaneous recording of the near-field maps of the nanocavity in collection-scanning mode [8][9][10][11] and interaction-scanning mode. 12,13,21 The first method is similar to the one used in classical aperture-SNOM measurements, and the probe is used to locally collect the electromagnetic field above the cavity ͓I SNOM ͑x , y , z͒ in Fig.…”

Trapping a single atom with a fraction of a photon using a photonic crystal nanocavity

“…This is because, whereas the mode volume of state-of-the-art macroscopic cavities is on the order of 10 5 μm 3 , a photonic crystal nanocavity typically has a mode volume of a cubic wavelength. Because of this small mode volume, a photonic crystal nanocavity can easily be tuned by bringing a nano-object into the near field of the cavity [10][11][12]. For experiments in cavity quantum electrodynamics [13][14][15], a single emitter needs to be brought into the near field of the cavity.…”