Publications by authors named "Muhammad Arshad Kamran"

11 Publications

  • Page 1 of 1

Revealing the optoelectronic properties of Re-based double perovskites using the Tran-Blaha modified Becke-Johnson with density functional theory.

J Mol Model 2020 May 28;26(6):158. Epub 2020 May 28.

School of Physical Science and Technology, Southwest University, Chongqing, 400715, China.

Density functional theoretical (DFT) calculations were carried out to explore the electronic and optical properties of double ordered BaNaReO, BaLiReO, and SrLiReO perovskites by employing the state-of-the-art exchange-correlation potential, i.e., Tran-Blaha modified Becke-Johnson for the electronic system. The calculated electronic band structures show an indirect band gap along with a semiconductor nature. Total and partial densities of state peaks were analyzed in light of effective contributions of various electronic states. The significant optical parameters, including the components of dielectric constant, the energy loss function, the absorption coefficient, the reflectivity spectra, the refractive index, and the extinction coefficient, were computed and discussed in details for radiation up to 14 eV. Finally, we studied the inter-band contributions from the optical characteristics. Our present study might be considered as first theoretical quantitative calculations of the optical and electronic behavior in the cubic phase of double perovskite materials based on rhenium.
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http://dx.doi.org/10.1007/s00894-020-04421-5DOI Listing
May 2020

Dual-Color Lasing Lines from EMPs in Diluted Magnetic Semiconductor CdS:NiI Structure.

Research (Wash D C) 2019 5;2019:6956937. Epub 2019 Nov 5.

Department of Physics, College of Science, Majmaah University, Al-Majmaah 11952, Saudi Arabia.

Have one ever seen a semiconductor that can issue two-color lasing lines? The diluted magnetic semiconductor (DMS) can do this. Here, we have observed dual lasing lines of 530 nm and 789 nm from a DMS structure of CdS:NiI, in which the excitonic magnetic polaron (EMP) and localized excitonic magnetic polaron (LEMP) are excitations out of ferromagnetic (NiS) nanocluster and NiI nanoclusters within CdS lattice; both of them could lead to the collective EMP state at high excitation and therein produce coherent emission lines simultaneously. This occurrence is due to the superposition of EMP near CdS bandedge and the combination of the charge-transfer band of (NiI) cluster with the LEMP within CdS lattice by overcoming the strong electron correlation of NiI cluster in a DMS structure, evidenced also by ab initio calculation. This finding opens a way to understand the collective behaviour of spin-coupled excitons in DMS and to find novel applications in the spin-related quantum technology.
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http://dx.doi.org/10.34133/2019/6956937DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6944495PMC
November 2019

Electronic structure and optical properties of TaNO: An ab initio study.

J Mol Graph Model 2019 11 10;92:296-302. Epub 2019 Aug 10.

School of Physical Science and Technology, Southwest University, Chongqing, 400715, China. Electronic address:

We performed ab initio calculations to study the structural and optoelectronic properties of simple and slab phase TaNO using density functional theory (DFT), in which the full potential augmented plane wave (FP-LAPW) method was implemented using the computational code Wien 2k. The modified Becke-Johnson potential (mBJ-GGA) was used for these calculations. The calculated band structure and electronic properties revealed an indirect bandgap for simple TaNO (3.2 eV) and a direct bandgap for slab TaNO (1.5 eV). The interband electronic transitions were investigated from the band structure, and transition peaks were observed from the imaginary part of the dielectric function. These transitions are due to Ta-p, N-p and O-p orbitals for simple TaNO and Ta-p, N-s as well as O-p orbitals for slab TaNO. The plasmon energy was related to the main peak of the energy loss function, which was approximately 10 eV. The static value of the dielectric constant and the refraction were close to the experimental values. In general, slab TaNO shows different properties and is more suitable for optoelectronic applications due to direct bandgap.
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http://dx.doi.org/10.1016/j.jmgm.2019.08.006DOI Listing
November 2019

Mn(II) Ions Assisted Near-Infrared Single-Mode Lasing from an Individual Mn-Doped CdS Nanobelts.

J Nanosci Nanotechnol 2019 Jul;19(7):4172-4177

Department of Physics, College of Science, Majmaah University, Al-Majmaah 11952, Saudi Arabia.

Tunable single-mode lasers are attractive for their potential applications in signal processing, optical communication, and displays. Here we present the Mn(II) ions assisted single-mode lasing occurring at near-infrared (NIR) band instead of the green emission band of CdS nanobelts (NBs) for the first time. Successful substation of Mn(II) ions at the tetrahedral Cd cites in the CdS matrix were confirmed by EPR. Light Mn(II) doping (≤1%) in CdS belts not only red-shifted the Raman modes but also increased crystallinity compared to pure CdS NBs due to strong excitons-phonon couplings. Up to 3 J · cm pumping fluence of ns laser, lightly doped CdS:Mn NBs show two photoluminescence (PL) emissions. First emission centered at 514.2 nm (green) corresponds to band-edge of CdS and an in-gap emission centered at 771.4 nm (NIR) corresponds to Mn(II) ions aggregates. After using intense excitation pulse, these NBs exhibited lasing at 791.4 nm with the lowest laser thresholds at 4.2 J · cm in the CdS system. This lasing action is further confirmed by lifetime kinetics. The results indicated that the lasing in these NBs involves the localised excitons magnetic polarons and Farby-Perot (F-P) optical resonant processes at room temperature.
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http://dx.doi.org/10.1166/jnn.2019.15834DOI Listing
July 2019

'Corrigendum: Role of Ni2+(d8) ions in electrical, optical and magnetic properties of CdS nanowires for optoelectronic and spintronic applications (2018 Nanotechnology 29 265602)'.

Nanotechnology 2018 Nov 15. Epub 2018 Nov 15.

Department of Physics, Majmaah University, Al Majma'ah, SAUDI ARABIA.

For the first time, 1D Ni ions doped CdS nanowires (NWs) were synthesized via chemical vapour deposition (CVD). The synthesized Cd0.886Ni0.114S NWs were single crystalline. We have reported here, investigation of optical, electrical and magnetic properties of prepared NWs for optoelectronic and spintronic applications. Successful incorporation of Ni ions in an individual CdS NW has been confirmed through several characterization tools: significant higher angle and phonon modes shift were observed in the XRD and Raman spectra. SEM-EDX and XPS analysis also confirmed the presence of Ni2+ ions. Room-temperature photoluminescence (RT-PL) showed multi-peaks: two emission peaks in the visible region centered at 517.1 nm (green), 579.2 nm (orange), and a broad-band near infrared (NIR) emission centered at 759.9 nm. Herein, the first peak showed 5 nm red-shift upon Ni2+ doping hinting the formation of exciton magnetic polarons (EMPs), and broad-NIR emission was observed in both chlorides and bromides which was assigned to d-d transition of Ni ions whose energy levels lie at 749.51 nm (13342 cm-1) and 750.98 nm (13316 cm-1) are very close to NIR emission. Orange emission was not only remained at same peak position but also its PL intensity significantly enhanced at 78 K and is assigned to d-d transition (3A2g → 1Eg) of Ni2+ ions. It was observed that 11.4% Ni2+ ions doping enhance the conductivity of our sample around 20 times and saturation magnetization (Ms) increases from 7.2 × 10-5 Am2/Kg to 1.17 × 10-4 Am2/Kg which shows promise for optoelectronic and spintronic applications.
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http://dx.doi.org/10.1088/1361-6528/aaf14cDOI Listing
November 2018

The aggregation of Mn, its d-d transition in CdS:Mn(II) nanobelts and bound magnetic polaron formation at room temperature.

Nanotechnology 2018 Oct 7;29(43):435702. Epub 2018 Aug 7.

Department of Physics, College of Science, Majmaah University, Majmaah 11952, Saudi Arabia.

Tuning the photoluminescence (PL) and magnetic properties of 1D semiconductor nanostructures is extremely important in processing light, improving the speed and storage capacity for optoelectronic and spintronic applications. Here, we have reported the 1D Cd Mn S (x = 0-0.102) nanobelts (NBs) and investigated their optical and magnetic properties. These NBs were synthesized by chemical vapor deposition method. The successful incorporation of Mn ions into an individual CdS NB has been confirmed through several characterization tools: SEM-EDX analysis, significant higher angle and phonon mode shifts were observed in the XRD and Raman spectra. Room-temperature PL showed two emission peaks at the near band edge. The first peak is related to exciton magnetic polaron (EMP) and the second one appeared on the low-energy side of the band edge emission and showed very large red-shift (∼33 nm) compared to EMP, which is attributed to bound magnetic polaron (BMP). BMP emission was detected for the first time in CdS low-dimensional nanostructures. Our study showed that Mn ions tuned CdS emission more than 400 nm (from 512 to 929 nm) covering the whole visible spectral region up to the near infrared region for the first time, and significantly boosted the room-temperature ferromagnetism, which shows promise for optoelectronic and spintronic applications.
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http://dx.doi.org/10.1088/1361-6528/aad894DOI Listing
October 2018

Role of Ni(d) ions in electrical, optical and magnetic properties of CdS nanowires for optoelectronic and spintronic applications.

Nanotechnology 2018 Jun 12;29(26):265602. Epub 2018 Apr 12.

Department of Physics, College of Science, Majmaah University Majmaah 11952, Saudi Arabia.

For the first time, 1D Ni ion doped CdS nanowires (NWs) were synthesized via chemical vapour deposition (CVD). The synthesized CdNiS NWs were single crystalline. We have reported here the investigation of optical, electrical and magnetic properties of prepared NWs for optoelectronic and spintronic applications. Successful incorporation of Ni ions in an individual CdS NW has been confirmed through several characterization tools: significantly higher angle and phonon mode shift were observed in the XRD and Raman spectra. SEM-EDX and XPS analysis also confirmed the presence of Ni ions. Room temperature photoluminescence (RT-PL) showed multiple peaks: two emission peaks in the visible region centered at 517.1 nm (green), 579.2 nm (orange), and a broad-band near infra-red (NIR) emission centered at 759.9 nm. The first peak showed 5 nm red shift upon Ni doping, hinting at the formation of exciton magnetic polarons (EMPs), and broad NIR emission was observed in both chlorides and bromides, which was assigned to d-d transition of Ni ions whose energy levels lying at 749.51 nm (13 342 cm) and 750.98 nm (13 316 cm) are very close to NIR emission. Orange emission not only remained at same peak position-its PL intensity was also significantly enhanced at 78 K; this was assigned to d-d transition (A → E) of Ni ions. It was observed that 11.4% Ni ion doping enhanced the conductivity of our sample around 20 times, and saturation magnetization (M) increased from 7.2 × 10 Am/Kg to 1.17 × 10 Am/Kg, which shows promise for optoelectronic and spintronic applications.
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http://dx.doi.org/10.1088/1361-6528/aabdc2DOI Listing
June 2018

Synthesis and Photoluminescence of Single-Crystalline Fe(III)-Doped CdS Nanobelts.

J Nanosci Nanotechnol 2016 Apr;16(4):4086-93

In this paper, we report the synthesis and optical properties of Fe(III) doped CdS nanobelts (NBs) via simple Chemical Vapor Deposition (CVD) technique to explore their potential in nano-optics. The energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) analysis manifested the presence of Fe(III) ions in the NBs subsequently confirmed by the peak shifting to lower phonon energies as recorded by Raman spectra and shorter lifetime in ns. Photoluminescence (PL) spectrum investigations of the single Fe(III)-doped CdS NBs depicted an additional PL peak centered at 573 nm (orange emission) in addition to the bandedge(BE) emission. The redshift and decrease in the BE intensity of the PL peaks, as compared to the bulk CdS, confirmed the quenching of spectra upon Fe doping. The synthesis and orange emission for Fe-doped CdS NBs have been observed for the first time and point out their potential in nanoscale devices.
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http://dx.doi.org/10.1166/jnn.2016.11033DOI Listing
April 2016

Synthesis of Novel Sea-Urchin-Like CdS and Their Optical Properties.

J Nanosci Nanotechnol 2015 Jun;15(6):4435-41

A novel morphology of CdS sea-urchin-like microstructures is synthesized by simple thermal evaporation process. Microstructures with average size of 20-50 μm are composed of single crystalline CdS nanobelts. The structural, compositional, morphological characterization of the product were examined by X-ray diffraction, energy dispersive X-ray spectroscopy, Raman spectroscopy, scanning electron microscope, transmission electron microscopy and selected area electron diffraction while optical properties are investigated by Photoluminescence spectroscopy and time-resolved Photoluminescence measurements. The tentative growth mechanism for the growth of sea-urchin-like CdS is proposed and described briefly. A strong green emission with a maximum around 517 nm was observed from the individual CdS microstructure at room temperature, which was attributed to band-edge emission of CdS. These Novel structures exhibit excellent lasing (stimulated emission) with low threshold (9.07 μJ cm(-2)) at room temperature. We analyze the physical mechanism of stimulated emission. These results are important in the design of green luminescence, low-threshold laser and display devices in the future.
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http://dx.doi.org/10.1166/jnn.2015.9790DOI Listing
June 2015

Tunable emission properties by ferromagnetic coupling Mn(II) aggregates in Mn-doped CdS microbelts/nanowires.

Nanotechnology 2014 Sep 2;25(38):385201. Epub 2014 Sep 2.

Beijing Key Laboratory of Nanophotonics & Ultrafine Optoelectronic Systems, Beijing Institute of Technology, Beijing 100081, People's Republic of China.

Tunable optical emission properties from ferromagnetic semiconductors have not been well identified yet. In this work, high-quality Mn(II)-doped CdS nanowires and micrometer belts were prepared using a controlled chemical vapor deposition technique. The Mn doping could be controlled with time, precursor concentration and temperature. These wires or belts can produce both tunable redshifted emissions and ferromagnetic responses simultaneously upon doping. The strong emission bands at 572, 651, 693, 712, 745, 768, 787 and 803 nm, due to the Mn(II) (4)T1((4)G)  → (6)A1((6)s) d-d transition, can be detected and accounted for by the aggregation of Mn ions at Cd sites in the CdS lattice at high temperature. These aggregates with ferromagnetism and shifted luminescence are related to the excitonic magnetic polaron (EMP) and localized EMP formations; this is verified by ab initio calculations. The correlation between aggregation-dependent optical emissions and ferromagnetic responses not only presents a new size effect for diluted magnetic semiconductors (DMSs), but also supplies a possible way to study or modulate the ferromagnetic properties of a DMS and to fabricate spin-related photonic devices in the future.
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http://dx.doi.org/10.1088/0957-4484/25/38/385201DOI Listing
September 2014

Tailoring of optical modes of semiconductor microcavities via metal and dielectric gratings.

Opt Lett 2012 Dec;37(24):5085-7

Beijing Key Laboratory of Nanophotonics & Ultrafine Optoelectronic Systems and School of Physics, Beijing Institute of Technology, Beijing 100081, China.

We investigate optical mode tailoring in a semiconductor microcavity with a metal grating on top and a dielectric grating (DG) on the bottom. Strong coupling between microcavity and grating-diffraction modes is explained in the Fano-picture. The Fano resonance shows a weak dependence upon grating height and duty ratio, but is strong upon grating period. The microcavity transmission line shapes are "S" and anti "S"-type for the metal and DGs, respectively. Together with these two types of Fano resonances, the transmission spectra have been tailored into very sharp peaks with FWHM being up to 0.1 nm. We prove that this optical mode tailoring method is quite applicable for other waveguide-grating structures too.
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http://dx.doi.org/10.1364/OL.37.005085DOI Listing
December 2012
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