Chemically-etched nanostructures and related devices

A wafer structure comprising:

• a first cladding layer and a second cladding layer;
• an intermediate active quantum nanostructure layer interposed between the first cladding layer and the second cladding layer;
• and
• at least one laterally etched recess made on one side of the wafer structure in the region of the intermediate active quantum nanostructure layer, said lateral etched recess defining a lateral protrusion of the first cladding layer and a lateral protrusion of the second cladding layer protruding with respect to the intermediate active quantum nanostructure layer.

A method of creating three-dimensional photonic crystals, the method comprising:

• providing a one-dimensional periodic structure including alternating layers of cladding and sacrificial layers;
• performing lithography on a top surface of the one-dimensional periodic structure to define two-dimensional photonic crystal patterns, and to obtain a backbone structure including alternating void spaces and walls, each wall including said alternating layers of cladding and sacrificial layers;
• and
• laterally etching at least one of said walls to partially remove the sacrificial layers sandwiched between two adjacent cladding layers and to obtain three-dimensional photonic crystals.

A photonic crystal double slab comprising:

• two photonic crystal membranes, the two photonic crystal membranes overlapping one another and being spaced apart by means of an intermediate gap;
• and
• a current aperture structure between the two photonic crystal membranes,
• wherein said intermediate gap is a lateral wet-chemically etched recess made in a sacrificial layer interposed between the two photonic crystal membranes.

A method of fabricating a photonic crystal laser comprising:

• providing two photonic crystal membranes, the two photonic crystal membranes overlapping one another;
• interposing a sacrificial active quantum nanostructure between the two photonic crystal membranes;
• laterally etching the sacrificial active quantum nanostructure to define a gap between the two photonic crystal membranes via microfabrication technologies;
• depositing top electrodes using photolithography;
• and
• etching holes through the two photonic crystal membranes using nano-fabrication technologies based on an electron-beam lithography.