Near-field light generator and thermally-assisted magnetic recording head

摘要

A near-field light generator includes a multilayer structure having a front end face. The multilayer structure includes a first dielectric layer, a second dielectric layer, a third dielectric layer, a first metal layer, and a second metal layer. The first metal layer is interposed between the first dielectric layer and the second dielectric layer. The second metal layer is interposed between the second dielectric layer and the third dielectric layer. Each of the first to third dielectric layers and the first and second metal layers has an end located in the front end face. The dielectric material used to form the first dielectric layer, the dielectric material used to form the second dielectric layer, and the dielectric material used to form the third dielectric layer have the same permittivity.

主权项

1. A near-field light generator comprising a multilayer structure having a front end face, and a core through which light is propagated, wherein
the multilayer structure includes a first dielectric layer, a second dielectric layer, a third dielectric layer, a first metal layer, and a second metal layer, the first metal layer is interposed between the first dielectric layer and the second dielectric layer, the second metal layer is interposed between the second dielectric layer and the third dielectric layer, each of the first to third dielectric layers and the first and second metal layers has an end located in the front end face, each of the first and second metal layers is formed of a metal material, each of the first to third dielectric layers is formed of a dielectric material, the dielectric material used to form the first dielectric layer, the dielectric material used to form the second dielectric layer, and the dielectric material used to form the third dielectric layer have the same permittivity, the near-field light generator is configured so that the first metal layer propagates a first surface plasmon, the second metal layer propagates a second surface plasmon, and the front end face generates near-field light based on the first and second surface plasmons, the core has an evanescent light generating surface that generates evanescent light based on the light propagated through the core, the first dielectric layer includes an interposition part interposed between the evanescent light generating surface and the first metal layer, and the first and second surface plasmons are excited based on the evanescent light generated from the evanescent light generating surface.