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It is a challenging task to fabricate thermally stable Photodetectors (PDs) working in visible light spectrum range due to the degradation in photoresponse characteristics. Herein, excellent performance parameters with photoresponsivity reached up to as high as 50 AW -1 , and ultrahigh specific detectivity in excess of 2.3×10 12 Jones have been obtained simultaneously in a single photodetector based on vertical MoS 2 (v-MoS 2 ) at a high temperature of 200°C. The TiO 2 interlay layer is ascribed as the main factor to enhance the PDs performances by reducing lattice mismatch between v-MoS 2 and substrate, separating photogenerated electron-hole pairs (EHPs), and the formation of the vertical MoS 2 nanostructures. Besides, the optoelectronics performances of the v-MoS 2 /TiO 2 heterostructures based field-effect transistor (FET) have also been examined under various operating temperatures, and the mechanism on how gate voltages affect the PDs performances has also been studied. In a word, the present fabricated v-MoS 2 /TiO 2 heterostructures based FET PDs will find practical applications in high-temperature environment.
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Stable Universal 1‐ and 2‐Input Single‐Molecule Logic Gates
Abstract Controllable single‐molecule logic operations will enable development of reliable ultra‐minimalistic circuit elements for high‐density computing but require stable currents from multiple orthogonal inputs in molecular junctions. Utilizing the two unique adjacent conductive molecular orbitals (MOs) of gated Au/S‐(CH2)3‐Fc‐(CH2)9‐S/Au (Fc = ferrocene) single‐electron transistors (≈2 nm), a stable single‐electron logic calculator (SELC) is presented, which allows real‐time modulation of output current as a function of orthogonal input bias (Vb) and gate (Vg) voltages. Reliable and low‐voltage (ǀVbǀ ≤ 80 mV, ǀVgǀ ≤ 2 V) operations of the SELC depend upon the unambiguous association of current resonances with energy shifts of the MOs (which show an invariable, small energy separation of ≈100 meV) in response to the changes of voltages, which is confirmed by electron‐transport calculations. Stable multi‐logic operations based on the SELC modulated current conversions between the two resonances and Coulomb blockade regimes are demonstrated via the implementation of all universal 1‐input (YES/NOT/PASS_1/PASS_0) and 2‐input (AND/XOR/OR/NAND/NOR/INT/XNOR) logic gates.
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- Award ID(s):
- 1916874
- PAR ID:
- 10445326
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 34
- Issue:
- 26
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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