1
|
Myers NM, Peña FJ, Cortés N, Vargas P. Multilayer Graphene as an Endoreversible Otto Engine. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13091548. [PMID: 37177093 PMCID: PMC10180394 DOI: 10.3390/nano13091548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 04/29/2023] [Accepted: 05/03/2023] [Indexed: 05/15/2023]
Abstract
We examine the performance of a finite-time, endoreversible Otto heat engine with a working medium of monolayer or multilayered graphene subjected to an external magnetic field. As the energy spectrum of multilayer graphene under an external magnetic field depends strongly on the number of layers, so too does its thermodynamic behavior. We show that this leads to a simple relationship between the engine efficiency and the number of layers of graphene in the working medium. Furthermore, we find that the efficiency at maximum power for bilayer and trilayer working mediums can exceed that of a classical endoreversible Otto cycle. Conversely, a working medium of monolayer graphene displays identical efficiency at maximum power to a classical working medium. These results demonstrate that layered graphene can be a useful material for the construction of efficient thermal machines for diverse quantum device applications.
Collapse
Affiliation(s)
- Nathan M Myers
- Department of Physics, Virginia Tech, Blacksburg, VA 24061, USA
| | - Francisco J Peña
- Departamento de Física, Universidad Técnica Federico Santa María, Av. España 1680, Valparaíso 11520, Chile
- Millennium Nucleus in NanoBioPhysics (NNBP), Av. España 1680, Valparaíso 11520, Chile
| | - Natalia Cortés
- Instituto de Alta Investigación, Universidad de Tarapacá, Arica Casilla 7D, Chile
- Department of Physics and Astronomy, and Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, OH 45701, USA
| | - Patricio Vargas
- Departamento de Física, CEDENNA, Universidad Técnica Federico Santa María, Av. España 1680, Valparaíso 11520, Chile
| |
Collapse
|
2
|
Ge Y, Fisher TS. First-principles calculations of the optical response of single-layer and bilayer armchair graphene nanoribbons. FRONTIERS IN NANOTECHNOLOGY 2022. [DOI: 10.3389/fnano.2022.999292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Electronic and optical properties of single-layer and bilayer armchair graphene nanoribbons are investigated using a first-principles method. Increased nanoribbon width reduces the band gap and causes a red shift in photon absorption energy. The 3n + 2 family of nanoribbons has the smallest band gaps and lowest onset photon absorption energy among the three families considered due to high π-conjugation indicated by exciton wavefunctions. We also compare the bilayer α and β alignments of armchair graphene nanoribbons with their single-layer counterparts. The extra layer of graphene reduces the band gap and onset photon absorption energy, and the difference between the α alignment and the single-layer configuration is more significant than that of the β alignment and the single layer. Our calculations indicate that the optical properties of graphene nanoribbons depend on the details of atomic structures, including nanoribbon width, edge alignment and number of layers. These characteristics are expected to be important in the design of optoelectronic devices.
Collapse
|
3
|
Lu D, Shanshan M, Zhu X, Da H. Temperature controllable Goos-Hänchen shift and high reflectance of monolayer graphene induced by BK7 glass grating. NANOTECHNOLOGY 2022; 33:485201. [PMID: 35994973 DOI: 10.1088/1361-6528/ac8b8c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 08/18/2022] [Indexed: 06/15/2023]
Abstract
BK7 glass has an unusual temperature-dependent refractive index and thickness, which provides a promising platform for uncovering the temperature-related optical phenomena and applications. Here, we theoretically demonstrate that monolayer graphene based BK7 glass grating structure has two Goos-Hänchen (GH) peaks with respective magnitudes of2564λand1993λ,and their corresponding reflectances are also high. The electromagnetic field distribution in this structure directly reveals that the enhanced GH shifts can be ascribed to the excitation of the guide mode resonances in the waveguide dielectric layer below BK7 glass grating structure and their high reflectances are granted by the constructive interferences between the reflected waves. In addition, the magnitudes of the GH peaks can be controlled by the temperature of BK7 glass as well as the chemical potential of monolayer graphene. We also evaluate the temperature sensing property of this structure based on the GH shifts and find that its maximum temperature sensitivity can be up to5.0017×104μm°C-1.The enhanced and controlled GH shift presented in monolayer graphene based BK7 glass grating structure shows promise for the applications, such as, optical sensors, temperature sensors, and optoelectronic detectors.
Collapse
Affiliation(s)
- Delian Lu
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing, Jiangsu, 210046, People's Republic of China; Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province, Nanjing 210023, People's Republic of China
| | - Ma Shanshan
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing, Jiangsu, 210046, People's Republic of China; Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province, Nanjing 210023, People's Republic of China
| | - Xiaojun Zhu
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing, Jiangsu, 210046, People's Republic of China; Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province, Nanjing 210023, People's Republic of China
| | - Haixia Da
- College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing, Jiangsu, 210046, People's Republic of China; Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province, Nanjing 210023, People's Republic of China
| |
Collapse
|
4
|
Liang N, Li Q, Pan G, Liu C, Liu Y. Carbon Material With Ordered Sub-Nanometer Hole Defects. Front Chem 2022; 10:858154. [PMID: 35386846 PMCID: PMC8979169 DOI: 10.3389/fchem.2022.858154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 03/01/2022] [Indexed: 11/13/2022] Open
Abstract
A holey carbon material with ordered sub-nanometer hole defects was synthesized from oxidative cyclodehydrogenation of a polyhexaphenylbenzene precursor. Band gap of around 2.2 eV is formed due to the narrow connection between the hexabenzocoronene subunits. It has weak interlayer interaction energy compared with graphene and shows easy dispersion in a wide range of solvents, surprisingly including water. Density functional theory calculations confirmd the excellent dispersion of this material in water. This new carbon material was then proved as effective support for various inorganic nanoparticles of small sizes. The supported iron nanoparticles showed enzyme-like catalysis behavior in nitrophenyl reduction reaction by NaBH4, exemplifying the great potential of this new material in catalysis.
Collapse
Affiliation(s)
- Nianjie Liang
- School of Chemistry, Beihang University, Beijing, China
| | - Qiaosheng Li
- School of Chemistry, Beihang University, Beijing, China
| | - Ganghuo Pan
- School of Chemistry, Beihang University, Beijing, China
| | - Chunxiang Liu
- School of Chemistry, Beihang University, Beijing, China
| | - Yuzhou Liu
- School of Chemistry, Beihang University, Beijing, China
- Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, China
- Beijing Shenyun Zhihe Technology Co., Ltd., Beijing, China
- *Correspondence: Yuzhou Liu,
| |
Collapse
|
5
|
Kumar A, Manjuladevi V, Gupta RK. Refractive index of graphene AA and AB stacked bilayers under the influence of relative planar twisting. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 34:015302. [PMID: 34614485 DOI: 10.1088/1361-648x/ac2d5f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 10/06/2021] [Indexed: 06/13/2023]
Abstract
The optical properties of graphene in monolayer and bilayer structure is essential for the development of optical devices viz surface plasmon resonance (SPR) based bio-sensors. The band structure of the twisted bilayer graphene (BLG) is remarkably different than the normal AA or AB stacking. This provides an opportunity to control the optical and electrical properties of BLG by applying an in-plane twist to one of the layer relative to other in a BLG system. Here, we calculated the refractive index (RI) of AA and AB stacking of BLG system using density functional theory. Though the spectrum for AA stacking shows some similarity with that of monolayer graphene, the spectrum for AB stacking was found to be remarkably different. The spectrum of AB stacked layer is red-shifted and the absorption peaks in low energy regime increases nearly by three-folds. A large dependency of the twist angle on RI of twisted BLG were found. Based on the calculation, a schematic of phase diagram showing material behavior of such twisted BLG systems as a function of twist angle and photon energy was constructed. The twisted AA stacked BLG shows largely dielectric behavior whereas the twisted AB stacked BLG shows predominately semimetallic and semiconducting behavior. This study presents a RI landscape of twisted BLG dependent on important parameters viz photon energy and inplane relative twist angle. Our studies will be very useful for the design and development of optical devices employing BLG systems particularly SPR based bio-sensors which essentially measures change in RI due to adsorption of analytes.
Collapse
Affiliation(s)
- Amrit Kumar
- Department of Physics, Birla Institute of Technology and Science, Pilani (BITS Pilani), 333031, India
| | - V Manjuladevi
- Department of Physics, Birla Institute of Technology and Science, Pilani (BITS Pilani), 333031, India
| | - R K Gupta
- Department of Physics, Birla Institute of Technology and Science, Pilani (BITS Pilani), 333031, India
| |
Collapse
|
6
|
Wang D, Madden S. Designing absorbers for graphene based mid-infrared wide band waveguide photodetectors. OPTICS EXPRESS 2021; 29:33850-33863. [PMID: 34809188 DOI: 10.1364/oe.438555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/21/2021] [Indexed: 06/13/2023]
Abstract
The mid-infrared (MIR) spectral region is of great importance in scientific and real-world applications ranging from detecting forming planets to identifying molecular species for industrial process control. Existing instrumentation to perform analyses is neither low cost nor compact, robust, or low power consumption, presenting opportunities for a planar integrated MIR sensing device to cost effectively detect and extract information on a widespread scale and in handheld devices. A key missing element in this vision is low cost waveguide photodetectors, which can cover the necessary wavelength range and are made with a wafer scale process. Graphene based detectors could fill this void. A parametric study is presented on broadband light absorption in graphene on waveguide devices of varied designs, index contrasts and dimensions. Generic design information is provided, and Genetic Annealing algorithms combined with Finite Element modal analysis provide a shortest design of 121 µm long that absorbs >90% of light from 1 to 10 µm, and a wide range of designs under 500 µm long. This shows for the first time that 2-D material based broadband waveguide MIR photodetectors could be viably integrated in MIR planar optics devices.
Collapse
|
7
|
Do TN, Shih PH, Chang CP, Lin CY, Lin MF. Rich magneto-absorption spectra of AAB-stacked trilayer graphene. Phys Chem Chem Phys 2016; 18:17597-605. [PMID: 27305856 DOI: 10.1039/c6cp02275h] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A generalized tight-binding model is developed to investigate the feature-rich magneto-optical properties of AAB-stacked trilayer graphene. Three intragroup and six intergroup inter-Landau-level (inter-LL) optical excitations largely enrich magneto-absorption peaks. In general, the former are much higher than the latter, depending on the phases and amplitudes of LL wavefunctions. The absorption spectra exhibit single- or twin-peak structures which are determined by quantum modes, LL energy spectra and Fermion distribution. The splitting LLs, with different localization centers (2/6 and 4/6 positions in a unit cell), can generate very distinct absorption spectra. There exist extra single peaks because of LL anti-crossings. AAB, AAA, ABA, and ABC stackings considerably differ from one another in terms of the inter-LL category, frequency, intensity, and structure of absorption peaks. The main characteristics of LL wavefunctions and energy spectra and the Fermi-Dirac function are responsible for the configuration-enriched magneto-optical spectra.
Collapse
Affiliation(s)
- Thi-Nga Do
- Department of Physics, National Cheng Kung University, Tainan, Taiwan.
| | - Po-Hsin Shih
- Department of Physics, National Cheng Kung University, Tainan, Taiwan.
| | - Cheng-Peng Chang
- Center for General Education, Tainan University of Technology, Tainan, Taiwan
| | - Chiun-Yan Lin
- Department of Physics, National Cheng Kung University, Tainan, Taiwan.
| | - Ming-Fa Lin
- Department of Physics, National Cheng Kung University, Tainan, Taiwan.
| |
Collapse
|
8
|
Abstract
Hofstadter butterfly of molybdenum disulfide monolayer resulting from multiple hoppings between 4d orbitals and intrinsic spin–orbit coupling.
Collapse
Affiliation(s)
- Yen-Hung Ho
- Department of Physics
- National Tsing Hua University
- Hsinchu 300
- Taiwan
- Department of Physics and Texas Center for Superconductivity
| | - Wu-Pei Su
- Department of Physics and Texas Center for Superconductivity
- University of Houston
- Houston
- USA
| | - Ming-Fa Lin
- Department of Physics
- National Cheng Kung University
- Tainan 701
- Taiwan
| |
Collapse
|
9
|
Sun J, Liu H, Chen X, Evans DG, Yang W, Duan X. Synthesis of graphene nanosheets with good control over the number of layers within the two-dimensional galleries of layered double hydroxides. Chem Commun (Camb) 2012; 48:8126-8. [DOI: 10.1039/c2cc33782g] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|