Abstract: Heterostructures include a layer of a two-dimensional material placed on a multiferroic layer. An ordered array of differing polarization domains in the multiferroic layer produces corresponding domains having differing properties in the two-dimensional material. When the multiferroic layer is ferroelectric, the ferroelectric polarization domains in the layer produce local electric fields that penetrate the two-dimensional material. The local electric fields modulate the charge carriers and carrier density on a nanometer length scale, resulting in the formation of lateral p-n or p-i-n junctions, and variations thereof appropriate for device functions.

Abstract: Heterostructures include a layer of a two-dimensional material placed on a multiferroic layer. An ordered array of differing polarization domains in the multiferroic layer produces corresponding domains having differing properties in the two-dimensional material. When the multiferroic layer is ferroelectric, the ferroelectric polarization domains in the layer produce local electric fields that penetrate the two-dimensional material. The local electric fields modulate the charge carriers and carrier density on a nanometer length scale, resulting in the formation of lateral p-n or p-i-n junctions, and variations thereof appropriate for device functions.

Abstract: The invention relates to heterostructures including a layer of a two-dimensional material placed on a multiferroic layer. An ordered array of differing polarization domains in the multiferroic layer produces corresponding domains having differing properties in the two-dimensional material. When the multiferroic layer is ferroelectric, the ferroelectric polarization domains in the layer produce local electric fields that penetrate the two-dimensional material. The local electric fields modulate the charge carriers and carrier density on a nanometer length scale, resulting in the formation of lateral p-n or p-i-n junctions, and variations thereof appropriate for device functions. Methods for producing the heterostructures are provided. Devices incorporating the heterostructures are also provided.

Abstract: A device for directly electrically generating and detecting the current-generated spin polarization in topological insulators, comprising a first and fourth contact on a layer of Bi2Se3 and a second contact comprising a ferromagnet/oxide tunnel barrier contact as a detector, and a third contact comprising nonmagnetic metal as a reference contact, a current to the first and fourth contact to produce a net spin polarization, and the spin polarization manifesting as a voltage between the second (magnetic) and third (reference) contacts.

Abstract: A device for directly electrically generating and detecting the current-generated spin polarization in topological insulators, comprising a first and fourth contact on a layer of Bi2Se3 and a second contact comprising a ferromagnet/oxide tunnel barrier contact as a detector, and a third contact comprising nonmagnetic metal as a reference contact, a current to the first and fourth contact to produce a net spin polarization, and the spin polarization manifesting as a voltage between the second (magnetic) and third (reference) contacts.

Abstract: A device for directly electrically generating and detecting the current-generated spin polarization in topological insulators, comprising a first and fourth contact on a layer of Bi2Se3 and a second contact comprising a ferromagnet/oxide tunnel barrier contact as a detector, and a third contact comprising nonmagnetic metal as a reference contact, a current to the first and fourth contact to produce a net spin polarization, and the spin polarization manifesting as a voltage between the second (magnetic) and third (reference) contacts.

Abstract: A 3C—SiC buffer layer on Si(001) comprising a porous buffer layer of 3C—SiC on a Si(001) substrate, wherein the porous buffer layer is produced through a solid state reaction, and wherein an amorphous carbon layer on the Si(001) substrate is deposited by magnetron sputtering of a C target at room temperature at a rate of 0.8 nm/min.

Abstract: The spin-Hall effect can be used to modulate the linear polarization of light via the magneto-optical Kerr effect. A central area of an outer surface of an added layer atop a spin Hall material is illuminated while simultaneously passing a modulated electric current through the material, so that reflected light has a new linear polarization that differs from the initial linear polarization to a degree depending on the amplitude of the modulated electric current.

Abstract: The invention relates to heterostructures including a layer of a two-dimensional material placed on a multiferroic layer. An ordered array of differing polarization domains and surface charges in the multiferroic layer produces corresponding domains having differing properties in the two-dimensional material. When the multiferroic layer is ferroelectric, the ferroelectric polarization domains in the layer produce local electric fields that penetrate the two-dimensional material. The local electric fields and surface charges can control the structural phase of the two-dimensional material, which in turn determines whether the two-dimensional material layer is insulating or metallic, has a band gap or no band gap, and whether it is magnetic or non-magnetic. Methods for producing the heterostructures are provided. Devices incorporating the heterostructures are also provided.

Abstract: The spin-Hall effect can be used to modulate the linear polarization of light via the magneto-optical Kerr effect. A acentral area of an outer surface of an added layer atop a spin Hall material is illuminated while simultaneously passing a modulated electric current through the material, so that reflected light has a new linear polarization that differs from the initial linear polarization to a degree depending on the amplitude of the modulated electric current.

Abstract: A device for directly electrically generating and detecting the current-generated spin polarization in topological insulators, comprising a first and fourth contact on a layer of Bi2Se3 and a second contact comprising a ferromagnet/oxide tunnel barrier contact as a detector, and a third contact comprising nonmagnetic metal as a reference contact, a current to the first and fourth contact to produce a net spin polarization, and the spin polarization manifesting as a voltage between the second (magnetic) and third (reference) contacts.

Abstract: The spin-Hall effect can be used to modulate the linear polarization of light via the magneto-optical Kerr effect. A material is illuminated while simultaneously passing a modulated electric current through the material, so that reflected light has a new linear polarization that differs from the initial linear polarization to a degree depending on the amplitude of the modulated electric current.

Abstract: A method for directly electrically generating and detecting spin polarization in topological insulators comprising depositing a first and fourth contact on a layer of Bi2Se3 and applying a current between the contacts, which creates a net spin polarization due to spin-momentum locking. A second (comprising ferromagnet/tunnel barrier) and third contact are deposited for detecting the spin polarization. A device for directly electrically generating and detecting the current-generated spin polarization in topological insulators, comprising a first and fourth contact on a layer of Bi2Se3 and a second contact comprising a ferromagnet/oxide tunnel barrier contact as a detector, and a third contact comprising nonmagnetic metal as a reference contact, a current to the first and fourth contact to produce a net spin polarization, and the spin polarization manifesting as a voltage between the second (magnetic) and third (reference) contacts.

Abstract: The invention relates to heterostructures including a layer of a two-dimensional material placed on a multiferroic layer. An ordered array of differing polarization domains and surface charges in the multiferroic layer produces corresponding domains having differing properties in the two-dimensional material. When the multiferroic layer is ferroelectric, the ferroelectric polarization domains in the layer produce local electric fields that penetrate the two-dimensional material. The local electric fields and surface charges can control the structural phase of the two-dimensional material, which in turn determines whether the two-dimensional material layer is insulating or metallic, has a band gap or no band gap, and whether it is magnetic or non-magnetic. Methods for producing the heterostructures are provided. Devices incorporating the heterostructures are also provided.

Abstract: The invention relates to heterostructures including a layer of a two-dimensional material placed on a multiferroic layer. An ordered array of differing polarization domains in the multiferroic layer produces corresponding domains having differing properties in the two-dimensional material. When the multiferroic layer is ferroelectric, the ferroelectric polarization domains in the layer produce local electric fields that penetrate the two-dimensional material. The local electric fields modulate the charge carriers and carrier density on a nanometer length scale, resulting in the formation of lateral p-n or p-i-n junctions, and variations thereof appropriate for device functions. Methods for producing the heterostructures are provided. Devices incorporating the heterostructures are also provided.

Abstract: A 3C—SiC buffer layer on Si(001) comprising a porous buffer layer of 3C—SiC on a Si(001) substrate, wherein the porous buffer layer is produced through a solid state reaction, and wherein an amorphous carbon layer on the Si(001) substrate is deposited by magnetron sputtering of a C target at room temperature at a rate of 0.8 nm/min.

Abstract: This disclosure describes a method of making a tunnel barrier-based electronic device, in which the tunnel barrier and transport channel are made of the same material—graphene. A homoepitaxial tunnel barrier/transport device is created using a monolayer chemically modified graphene sheet as a tunnel barrier on another monolayer graphene sheet. This device displays enhanced spintronic properties over heteroepitaxial devices and is the first to use graphene as both the tunnel barrier and channel.

Abstract: This disclosure describes a method of making a tunnel barrier-based electronic device, in which the tunnel barrier and transport channel are made of the same material—graphene. A homoepitaxial tunnel barrier/transport device is created using a monolayer chemically modified graphene sheet as a tunnel barrier on another monolayer graphene sheet. This device displays enhanced spintronic properties over heteroepitaxial devices and is the first to use graphene as both the tunnel barrier and channel.

Abstract: A method of making a SiC buffer layer on a Si substrate comprising depositing an amorphous carbon layer on a Si(001) substrate, controlling the thickness of the amorphous carbon layer by controlling the time of the step of depositing the amorphous carbon layer, and forming a deposited film. A 3C—SiC buffer layer on Si(001) comprising a porous buffer layer of 3C—SiC on a Si substrate wherein the porous buffer layer is produced through a solid state reaction.

Abstract: This disclosure describes a method of making a tunnel barrier-based electronic device, in which the tunnel barrier and transport channel are made of the same material—graphene. A homoepitaxial tunnel barrier/transport device is created using a monolayer chemically modified graphene sheet as a tunnel barrier on another monolayer graphene sheet. This device displays enhanced spintronic properties over heteroepitaxial devices and is the first to use graphene as both the tunnel barrier and channel.