10 results on '"Datta, Swarnab"'
Search Results
2. Nonlinear optical properties of doped GaAs quantum dot modulated by noise: Role of impurity spread.
- Author
-
Datta, Swarnab, Bhakti, Bhaskar, Pal, Aniruddha, and Ghosh, Manas
- Subjects
- *
QUANTUM dots , *OPTICAL properties , *WHITE noise , *AUDITING standards , *RANDOM noise theory , *OPTICAL susceptibility - Abstract
This paper explores the role of spatial extension of impurity (SEI) on two nonlinear optical (NLO) properties and two other related properties of impurity doped GaAs quantum dot (QD). The NLO properties include the electro-optic effect (EOE) and the third-order nonlinear optical susceptibility (TONOS) whereas the other two related properties being total optical dielectric function (TODF) and the intraband transition lifetime (ITL). The study also involves Gaussian white noise (GWN) which has been introduced to the doped QD through additive and multiplicative pathways. The investigation unveils the subtle interplay between GWN and SEI which ultimately fine-tunes the said NLO properties. TODF, EOE and TONOS manifest red-shift with enhancement of SEI both with and without GWN. The ITL, on the other hand, exhibits monotonic growth with increase in SEI under all conditions. Moreover, the application of GWN causes noticeable quenching of the NLO properties. And the quenching becomes more stringent in presence of multiplicative noise than its additive counterpart. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Role of Spatial Impurity Spread on the Transition Dynamics of Doped GaAs Quantum Dot in Presence of Noise.
- Author
-
Datta, Swarnab, Bhakti, Bhaskar, and Ghosh, Manas
- Subjects
- *
QUANTUM dots , *AUDITING standards , *WHITE noise , *GALLIUM arsenide , *RANDOM noise theory , *NOISE - Abstract
The present study thoroughly explores the time‐average population transfer rate (TAPTR) of impurity‐doped GaAs quantum dot (QD) pursuing the change in the spatial impurity spread (SIS). The said excitation rate is studied under the influence of Gaussian white noise (GWN). The rise of the ground‐state electronic density takes place due to different types of time‐changing fluctuations, viz. simple sinusoidal field, time‐dependent confinement potential, and time‐dependent magnetic field. GWN couples with the QD by additive and multiplicative modes. In this work, the joint influence of SIS and GWN and its pathway of inclusion and the nature of the time‐dependent perturbations are examined on the attributes of the TAPTR. The TAPTR curves are composed of steadfast rise, steadfast diminish, maximization (relevant to generation of large nonlinear optical properties), minimization, and saturation (suggesting dynamic freezing). The findings elucidate the means of fine‐tuning the TAPTR among the doped GaAs QD eigenstates in presence of noise, when the SIS undergoes a gradual change. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
4. Population Transfer Among the Quantum Dot Eigenstates Driven by Time‐dependent Anharmonic Potential: Role of Noise.
- Author
-
Datta, Swarnab, Arif, Sk. Md., Roy, Debi, and Ghosh, Manas
- Subjects
- *
QUANTUM dots , *WHITE noise , *RANDOM noise theory , *NOISE , *ANHARMONIC motion - Abstract
The study meticulously inspects the time‐average excitation rate (TAER)of lowest energy state electronic probability of GaAs quantum dot (QD)to the higher energy states. The excitation occurs as the anharmonic potential(a part of QD confinement) starts varying with time either periodicallyor randomly. The anharmonic potential is characterized by either evenor oddparity. Gaussian white noise (GWN)has also been introduced to the QD either via additiveor multiplicativemode. The study announces that the coupled impact of the given physical quantity, the symmetry of the anharmonicity, presence/absence of noise, the route of entrance of noise, and the nature of time progress of anharmonicity constant, ultimately regulates and fine‐tunes the attributes of the TAER diagrams. The TAER diagrams comprise of regular rise, regular fall, maximization (pertinent to production of high value of nonlinear optical (NLO) properties), minimization and saturation (pertinent to dynamic freezing). The outcomes of the study seem to be recognizable in various applications of devices containing QD. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
5. External Field‐induced Transitions in Quantum Dot: Role of Noise‐anharmonicity Interplay.
- Author
-
Datta, Swarnab, Arif, Sk. Md., Roy, Debi, and Ghosh, Manas
- Subjects
- *
QUANTUM transitions , *QUANTUM dots , *WHITE noise , *RANDOM noise theory , *ANHARMONIC motion , *OPTICAL properties - Abstract
This work scrutinizes the time‐average excitation rate (TAER) among the GaAs quantum dot (QD) eigenstates under the aegis of Gaussian white noise (GWN) and the parity of the anharmonic potential (odd/even). GWN connects with the system by additive or multiplicative mode. The said excitation of the ground state population has been triggered by an external field which may be a polychromatic radiation field (PRF), or pulsed field (PF) or chirped pulsed field (CPF). The study reveals the subtle nuances of the interplay between noise (additive or multiplicative), anharmonicity (odd or even) and the external field (PRF, PF or CPF) that finally govern the attributes of the TAER diagrams. The TAER profiles exhibit persistent growth, persistent decline, maximization (important in view of production of prominent nonlinear optical properties), minimization and saturation (relevant to the dynamic freezing). The findings appear useful for regulating the TAER among the GaAs QD eigenstates which have substantial technological relevance. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
6. Excitation Dynamics Among Impurity Doped Quantum Dot Eigenstates in a Polychromatic Field: Role of Gaussian White Noise.
- Author
-
Datta, Swarnab, Arif, Sk. Md., Roy, Debi, and Ghosh, Manas
- Subjects
- *
RANDOM noise theory , *QUANTUM dots , *EXCITED states , *WHITE noise , *RADIATION - Abstract
Current study focuses on realizing the role of Gaussian white noise (GWN) and external sinusoidal polychromatic radiation field (PRF) on the time‐average excitation rate (TAER) of impurity doped quantum dot (QD). The PRF induces the transfer of electronic population from the ground state to the excited states in course of time‐evolution. The PRF has been envisaged to be composed of four component fields that maintain either a prime or a non‐prime frequency ratio. GWN couples with the system additively and multiplicatively. The study highlights the role of various physical parameters, presence of noise, mode of application of noise and the features of PRF (amplitude, phase and type of frequency ratio of the components) in shaping the TAER profiles. The TAER profiles have been found to be enriched with steady growth, steady decline, maximization (useful for obtaining large nonlinear optical response), minimization and saturation (the dynamic freezing). The study reveals promising scope of obtaining desired TAER of doped QD by judicious adjustment/regulation of several control parameters which may bear serious technological implications. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
7. Analyzing Time‐Average Excitation Rate Among Quantum Dot Eigenstates Triggered by Time‐Dependent Noise Strength.
- Author
-
Datta, Swarnab, Arif, Sk. Md., Roy, Debi, and Ghosh, Manas
- Subjects
- *
QUANTUM dots , *WHITE noise , *RANDOM noise theory , *NOISE , *PHYSICAL constants , *DOPING agents (Chemistry) - Abstract
Present investigation rigorously explores the time‐average excitation rate (TAER) of ground‐state electronic population of GaAs quantum dot (QD) to the excited eigenstates. The QD confinement potential contains Gaussian impurity (the dopant) and Gaussian white noise (GWN). GWN can be categorized as either additive or multiplicative depending upon its way of attachment to the doped QD. The excitation occurs as soon as the noise strength begins fluctuating with time in periodic or random manner. The study highlights the coupled influence of the varying physical quantity, presence/absence of noise, the mode of attachment of noise to QD, and the nature of time‐fluctuation of the noise strength (periodic/random), and finally harnesses and tailors the features of the TAER profiles. The TAER plots unveil steady rise, steady fall, maximization (linked with the emergence of large nonlinear optical response), minimization, and saturation (linked with dynamic freezing). The findings appear to be significant in the practical usage of QD‐based devices. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
8. Exploring Shannon entropy and heat capacity of doped GaAs quantum dot under the influence of noise.
- Author
-
Bhakti, Bhaskar, Datta, Swarnab, and Ghosh, Manas
- Subjects
- *
UNCERTAINTY (Information theory) , *HEAT capacity , *THERMODYNAMICS , *RANDOM noise theory , *WHITE noise , *ENTROPY - Abstract
Present enquiry explores the Shannon entropy and the corresponding heat capacity of G a A s quantum dot (QD) which is doped with Gaussian impurity and under the aegis of Gaussian white noise (GWHN). GWHN may take additive and multiplicative routes for its entrance to the doped QDs. The enquiry analyzes the features of temperature-dependence of above thermodynamic properties and also the effect of various physical parameters on them at a given temperature. The study reveals some kind of complex interplay involving the temperature zone, presence/absence of GWHN, mode of application of GWHN and the particular physical parameter concerned which ultimately shapes the profiles of entropy and heat capacity. Often, the study reveals competitive behavior between thermal disorder and spatial disorder which noticeably affects the said thermal properties. Moreover, the study also highlights some unusual behavior in the entropy profiles only under multiplicative noise of high noise strength. • Shannon entropy and heat capacity of GaAs quantum dot (QD) are studied under the influence of Gaussian white noise (GWN). • The QD contains Gaussian impurity. • GWN is applied additively and multiplicatively. • Role of various physical parameters on the thermodynamic properties has been explored. • The mode of application of GWN also modulates the thermodynamic properties. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Tuning the magnetocaloric effect in GaAs quantum dot under the aegis of noise-anharmonicity interplay.
- Author
-
Bhakti, Bhaskar, Datta, Swarnab, and Ghosh, Manas
- Subjects
- *
MAGNETOCALORIC effects , *QUANTUM dots , *WHITE noise , *RANDOM noise theory , *AUDITING standards , *GALLIUM arsenide - Abstract
Present study rigorously scrutinizes the magnetocaloric effect (MCE) of G a A s quantum dot (QD) under the simultaneous influence of anharmonicity and Gaussian white noise (GWHN). The parity of the anharmonic potential, the route of introduction of GWHN and the QD confinement interplay delicately to fine-tune the MCE. Anharmonicity of odd (even) parity diminishes (augments) the confinement of the system with respect to the anharmonicity-free state. Generally, multiplicative noise brings in larger deviation of MCE (from the noise-free state) than additive noise. Additionally, additive (multiplicative) noise depletes (enhances) the magnitude of MCE in comparison with the noise-free values. • Magnetocaloric effect (MCE) of GaAs quantum dot (QD) is studied under the influence of Gaussian white noise (GWHN). • The QD contains anharmonicity of odd and even parities. • GWHN is applied additively and multiplicatively. • Role of noise-anharmonicity interplay on the MCE has been explored. • The mode of application of GWHN and the parity of anharmonic potential modulate the MCE. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
10. Pulsed field induced excitation in impurity doped quantum dot: Interplay with Gaussian white noise.
- Author
-
Datta, Swarnab, Arif, Sk. Md., Roy, Debi, and Ghosh, Manas
- Subjects
- *
RANDOM noise theory , *QUANTUM dots , *DISCONTINUOUS functions , *WHITE noise , *CONTINUOUS functions - Abstract
Current study strives to realizing the role of Gaussian white noise (GWN) and external pulsed field (PF) on the time-average excitation rate (TAER) of impurity doped quantum dot (QD). The PF is characterized by a pulse shape function which may be continuous or discontinuous with time. In the present study we invoke sinusoidal and triangular shape functions as continuous ones and regular telegraphic and random telegraphic shape functions as discontinuous ones. GWN links with the system additively and multiplicatively. The study emphasizes on analyzing the role of various physical parameters, application of noise, pathway of application of noise and the attributes of the PF (amplitude, phase, shape and the number of pulses) in designing the TAER profiles. The TAER profiles come out to be comprising of features like persistent rise, persistent fall, maximization (useful for attaining large nonlinear optical response), minimization and saturation (the dynamic freezing). [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.