A method of fabricating a multi-junction photosensitive device is provided. The method may include fabricating at least two photoactive layers, wherein at least one photoactive layer is fabricated on a transparent substrate, and at least one photoactive layer is fabricated on a reflective substrate, patterning at least one optical filter layer on at least one photoactive layer fabricated on a transparent substrate, and bonding the at least two photoactive layers using cold weld or van der Waals bonding. A multi-junction photosensitive device is also provided. The device may have at least two photoactive layers, and at least one optical filter layer, wherein at least two layers are bonded using cold weld or van der Waals bonding. The optical filter layer may be a Distributed Bragg Reflector.

A tandem photovoltaic device includes: a tunnel junction between an upper cell unit and a lower cell unit. The lower cell unit is a crystalline silicon cell. The tunnel junction includes: a carrier transport layer, a crystalline silicon layer, and an intermediate layer located between the carrier transport layer and the crystalline silicon layer. The carrier transport layer is a metal oxide layer. The intermediate layer includes a tunneling layer. The crystalline silicon layer has a doping concentration greater than or equal to 10.sup.17 cm.sup.?3. The carrier transport layer is in direct contact with a shadow surface of the upper cell unit. If the crystalline silicon layer is a p-type crystalline silicon layer, a first energy level is close to a second energy level. If the crystalline silicon layer is an n-type crystalline silicon layer, a third energy level is close to a fourth energy level.

A tandem photovoltaic device includes: a tunnel junction between an upper cell unit and a lower cell unit. The lower cell unit is a crystalline silicon cell. The tunnel junction includes: a carrier transport layer, a crystalline silicon layer, and an intermediate layer located between the carrier transport layer and the crystalline silicon layer. The carrier transport layer is a metal oxide layer. The intermediate layer includes a tunneling layer. The crystalline silicon layer has a doping concentration greater than or equal to 10.sup.17 cm.sup.?3. The carrier transport layer is in direct contact with a shadow surface of the upper cell unit. If the crystalline silicon layer is a p-type crystalline silicon layer, a first energy level is close to a second energy level. If the crystalline silicon layer is an n-type crystalline silicon layer, a third energy level is close to a fourth energy level.

A solar cell comprising a silicon substrate and a layered structure arranged on a surface of the silicon substrate, the layered structure comprising; a first layer comprising a percentage of crystalline material arranged within an amorphous matrix, the first layer being arranged on the surface of the silicon substrate; a second layer comprising a percentage of crystalline material arranged within an amorphous matrix, the second layer being interposed between the first layer and the surface of the silicon substrate; wherein the percentage of crystalline material in the first layer is greater than the percentage of crystalline material in the second layer.

A solar cell comprising a silicon substrate and a layered structure arranged on a surface of the silicon substrate, the layered structure comprising; a first layer comprising a percentage of crystalline material arranged within an amorphous matrix, the first layer being arranged on the surface of the silicon substrate; a second layer comprising a percentage of crystalline material arranged within an amorphous matrix, the second layer being interposed between the first layer and the surface of the silicon substrate; wherein the percentage of crystalline material in the first layer is greater than the percentage of crystalline material in the second layer.

A space-grade solar array has a plurality of solar cells with an electrically conductive adhesive between a back side of each diced solar cell and a printed circuit board. A method of manufacturing such a space grade solar array includes dicing a multi-junction solar wafer having a plurality of solar cells to form a plurality of diced multi-junction solar cells, and positioning an electrically conductive adhesive between a back side of each diced solar cell and a printed circuit board; and adhesively securing the diced solar cells onto the printed circuit board via the adhesive.

Two-dimensional (2D) crystals have renewed opportunities in artificial lattice design and assembly without the constraints of epitaxy. However, the lack of thickness control in exfoliated van der Waals (vdW) layers prevents realization of repeat units with high fidelity. Uniform, wafer-scale samples permits engineering of both electronic and optical dispersions in stacks of disparate 2D layers with multiple repeating units. Systems, methods, and devices present optical dispersion engineering in a superlattice structure including alternating layers of 2D excitonic chalcogenides and dielectric insulators. Examples demonstrate >90% narrowband absorption in <4 nm active layer excitonic absorber medium at room temperature, concurrently with enhanced photoluminescence in cm.sup.2 samples. These superlattices show evidence of strong light-matter coupling and exciton-polariton formation with geometry-tunable coupling constants. The results demonstrate proof of concept structures with engineered optical properties and pave the way for a broad class of scalable, designer optical metamaterials from atomically-thin layers.

Two-dimensional (2D) crystals have renewed opportunities in artificial lattice design and assembly without the constraints of epitaxy. However, the lack of thickness control in exfoliated van der Waals (vdW) layers prevents realization of repeat units with high fidelity. Uniform, wafer-scale samples permits engineering of both electronic and optical dispersions in stacks of disparate 2D layers with multiple repeating units. Systems, methods, and devices present optical dispersion engineering in a superlattice structure including alternating layers of 2D excitonic chalcogenides and dielectric insulators. Examples demonstrate >90% narrowband absorption in <4 nm active layer excitonic absorber medium at room temperature, concurrently with enhanced photoluminescence in cm.sup.2 samples. These superlattices show evidence of strong light-matter coupling and exciton-polariton formation with geometry-tunable coupling constants. The results demonstrate proof of concept structures with engineered optical properties and pave the way for a broad class of scalable, designer optical metamaterials from atomically-thin layers.

An apparatus and method pertaining to a perpetual energy harvester. The harvester absorbs ambient infrared radiation and provides continual power regardless of the environment. The device seeks to harvest the largely overlooked blackbody radiation through use of a semiconductor thermal harvester.

An apparatus and method pertaining to a perpetual energy harvester. The harvester absorbs ambient infrared radiation and provides continual power regardless of the environment. The device seeks to harvest the largely overlooked blackbody radiation through use of a semiconductor thermal harvester.