USA As Represented by Secretary of the Navy

Adam L Friedman

Berend T Jonker

F Keith Perkins

Jeremy T Robinson

Paul M Campbell

Olaf M J Van 't Erve

Aubrey T Hanbicki

James C Culbertson

Brian H Houston

Connie H Li

Jeffrey W Baldwin

Keith E Whitener

Bernard R Matis

Steven P Bennett

James S Burgess

Felipe Bulat-Jara

Olaf M T Van 't Erve

Glenn Jernigan

Olaf M J Van't Erve

Enrique Cobas

Optical and electronic detection of chemicals, and particularly strong electron-donors, by 2H to 1T phase-based transition metal dichalcogenide (TMD) films, detection apparatus incorporating the TMD films, methods for forming the detection apparatus, and detection systems and methods based on the TMD films are provided. The detection apparatus includes a 2H phase TMD film that transitions to the 1T phase under exposure to strong electron donors. After exposure, the phase state can be determined to assess whether all or a portion of the TMD has undergone a transition from the 2H phase to the 1T phase. Following detection, TMD films in the 1T phase can be converted back to the 2H phase, resulting in a reusable chemical sensor that is selective for strong electron donors.

2H to 1T phase based transition metal dichalcogenide sensor for optical and electronic detection of strong electron donor chemical vapors

A metamagnetic tunneling-based spin valve device for multistate magnetic memory comprising an electronic memory logic element with four stable resistance states. A metamagnetic tunneling-based spin valve device for multistate magnetic memory comprising a layer of a metamagnetic material, a layer of a nonmagnetic material on the layer of a metamagnetic material, and a layer of a ferromagnetic material on the layer of a nonmagnetic material. A method of making a metamagnetic tunneling-based spin valve device for multistate magnetic memory.

Multistate magnetic memory element using metamagnetic materials

A method of making a low dimensional material chemical vapor sensor comprising providing a monolayer of a transition metal dichalcogenide, applying the monolayer to a substrate, applying a PMMA film, defining trenches, and placing the device in a n-butyl lithium (nbl) bath. A low dimensional material chemical vapor sensor comprising a monolayer of a transition metal dichalcogenide, the monolayer applied to a substrate, a region or regions of the transition metal dichalcogenide that have been treated with n-butyl lithium, the region or regions of the transition metal dichalcogenide that have been treated with n-butyl lithium have transitioned from a semiconducting to metallic phase, metal contacts on the region or regions of the transition metal dichalcogenide that have been treated with the n-butyl lithium.

2H/1T phase contact engineering for high performance transition metal dichalcogenide chemical vapor sensors

A homoepitaxial, ultrathin tunnel barrier-based electronic device in which the tunnel barrier and transport channel are made of the same material&#x2014;graphene.

Homoepitaxial tunnel barriers with hydrogenated graphene-on-graphene for room temperature electronic device applications

Process for forming homoepitaxial tunnel barriers with hydrogenated graphene-on-graphene for room temperature electronic device applications

A graphene compound made from the method of preparing graphene flakes or chemical vapor deposition grown graphene films on a SiO/Si substrate; exposing the graphene flakes or the chemical vapor deposition grown graphene film to hydrogen plasma; performing hydrogenation of the graphene; wherein the hydrogenated graphene has a majority carrier type; creating a bandgap from the hydrogenation of the graphene; applying an electric field to the hydrogenated graphene; and tuning the bandgap.

Hydrogenated graphene with surface doping and bandgap tunability

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&#x2014;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.

Homoepitaxial tunnel barriers with functionalized graphene-on-graphene and methods of making

A method of introducing a bandgap in single layer graphite on a SiOsubstrate comprising the steps of preparing graphene flakes and CVD grown graphene films on a SiO/Si substrate and performing hydrogenation of the graphene. Additionally, controlling the majority carrier type via surface adsorbates.

Surface doping and bandgap tunability in hydrogenated graphene

A method of making a low-dimensional material chemical vapor sensor comprising exfoliating MoS, applying the monolayer flakes of MoSonto a SiO/Si wafer, applying a methylmethacrylate (MMA)/polymethylmethacrylate (PMMA) film, defining trenches for the deposition of metal contacts, and depositing one of Ti/Au, Au, and Pt in the trench and resulting in a MoSsensor. A low-dimensional material chemical vapor sensor comprising monolayer flakes of MoS, trenches in the SiO/Si wafer, metal contacts in the trenches, and thereby resulting in a MoSsensor. A full spectrum sensing suite comprising similarly fabricated parallel sensors made from a variety of low-dimensional materials including graphene, carbon nanotubes, MoS, BN, and the family of transition metal dichalcogenides. The sensing suites are small, robust, sensitive, low-power, inexpensive, and fast in their response to chemical vapor analytes.

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Silver Spring, MD, United States of America

Adam L Friedman