http://localhost:8080/xmlui/handle/123456789/96 2026-05-20T06:58:23Z 2026-05-20T06:58:23Z Deepak, Deepak http://localhost:8080/xmlui/handle/123456789/6083 2026-04-21T06:57:52Z 2024-10-01T00:00:00Z

A Theoretical Study of Non Classical Features of Different Engineered Quantum States Deepak, Deepak This comprehensive theoretical study investigates different aspects of engineered quantum states, focusing on their non-classical features. The thesis comprises ten chapters, each contributing valuable insights to our understanding of quantum phenomena. The study begins with an introduction in Chapter 1, providing a brief overview of the research conducted during the specified period. Further, the literature review and methodology for the research is given in Chapter 2 and 3. Following this, Chapter 4 meticulously explores lower- versus higher-order nonclassicalities for a coherent superposed quantum state. Coherent states, conventionally defined in various ways, are analyzed here after operating a superposition of field operators. This chapter uncovers nuanced insights into both lower and higherorder non-classical properties using a set of nonclassicality witnesses. In Chapter 5, the focus shifts to the detection of nonclassicality and non-Gaussianity of a coherent superposed quantum state. The coherent superposed quantum state (CSQS), obtained through a coherent superposition of field operators, is examined for its nonclassical and non-Gaussian characteristics. The computation of various criteria including the Wigner function, linear entropy, Wigner logarithmic negativity, and skew information-based measures are employed to provide a comprehensive analysis. Chapter 6 undertakes a comparison between higher-order nonclassicalities of SUP-engineered coherent and thermal states. An experimentally accessible superposition (SUP) operator is applied to coherent and thermal quantum states, resulting in SUP-operated coherent states (SOCS) and SUP-operated thermal states (SOTS). This chapter presents a comparative analysis of the higher-order non-classical properties exhibited by SOCS and SOTS, contributing valuable insights for potential experimental verification. Chapter 7 delves into a comparative study of higher-order nonclassicalities of photon-added-then-subtracted and photon-subtracted-then-added quantum states. Photonmanipulated thermal and coherent states are examined for both higher and lowerorder non-classical features. The outcomes highlight the striking non-classical characteristics exhibited by the considered states and emphasize the preference for specific photon operations that enhance non-classicality. In Chapter 8, the study concentrates to explore the interplay between nonclassicality and quantum non-Gaussianity of photon-subtracted displaced Fock states. A quantitative investigation is conducted, considering the impact of the number of subiv tracted photons and the Fock parameter on nonclassical and quantum non-Gaussian characteristics. The dynamics of the Wigner function under a photon loss channel is analyzed to record the dissipation due to interaction with a vacuum reservoir as well as inefficient detectors with efficiency coefficient η = 1−T. Chapter 9 switches the focus to the realistic continuous-variable quantum teleportation using a displaced Fock state channel. Ideal and non-ideal continuousvariable quantum teleportation protocols are investigated by employing an entangled displaced Fock state resource. This chapter provides insights into the challenges and optimizations for successful teleportation, considering factors such as reflectivity, gain factor, mode damping, and the number of thermal photons. The final chapter, Chapter 10 offers a conclusive summary of the entire research work and outlines potential avenues for future exploration and investigation. This thesis altogether enriches our understanding of the non-classical features of different engineered quantum states, paving the way for advancements in quantum information processing and technology. DR. ARPITA CHATTERJEE

2024-10-01T00:00:00Z Preeti, Preeti http://localhost:8080/xmlui/handle/123456789/6082 2026-04-21T06:53:59Z 2025-05-01T00:00:00Z

Applications of Queuing Theory and Machine Learning Techniques in Healthcare Preeti, Preeti This thesis focuses on the application of queuing theory and machine learning techniques in healthcare management system, a field where optimization of resources is very crucial. Efficient management of hospital resources such as hospital beds, machines, equipments and staff can significantly impact both costs and patient outcomes. Having too many resources can lead to overhead expenses, while insufficient resources may result in critical situations, such as a shortage of beds during peak times. Therefore, predicting the required number of resources is important, especially when there is sudden disease outbreaks or pandemics, which pose challenges to hospital management. Queuing theory has a lots of applications in healthcare. For instance, it can optimize resource allocation in various departments, such as pharmacy units, Pediatrics, Intensive care units and emergency departments. We have utilized open Jackson queuing networks to reduce waiting times in pharmacies. Along with using open jackson queuing networks, we have also used simulation modelling and a comparison between the results obtained via the two different techniques of queuing theory and simulation has been done. Similarly, queuing models have proven effective in calculating the waiting time and other performance measures of customers in ultrasound and tomography labs. A mathematical model namely SEIRD model (Susceptible, Exposed, Infected, Recovered, Dead), which is particularly useful for studying dynamics of various pandemics, such as malaria and COVID-19. This model helps in forecasting number of patients and understanding disease spread. By incorporating such kind of mathematical models into healthcare management system, we can enhance decision-making and resource planning, ultimately improving efficiency and patient care. Next in the processing of improving healthcare services with the help of queuing theory and machine learning techniques, we focused on a pathology laboratory experiencing very high volumes of samples, leading to a considerable amount of delays in test results. This laboratory was chosen due to its extensive sample database, which allowed us to explore potential improvements. After investigation, we found that predicting turnaround time (TAT) and informing patients in advance could definitely enhance their experience. By better managing the idle time between a patient’s arrival and delivery of reports, we can optimize the process. Moreover, patients generally face decisions based on the expected waiting time for their results. If a laboratory’s turnaround time is too long, patients might opt for a faster and better alternative. Our predicted TAT can provide valuable information to help patients make more informed choices based on their priorities, such as cost versus speed of service. We utilized machine learning models to predict TAT in the laboratory setting and we iv realized that these models can also be used in distinguishing between in-care and out-care patients. We worked with a dataset that included demographic information (such as gender, age, and height) of patients and blood test results (such as blood sugar levels, body temperature, HB) to determine whether a patient requires in-care or out-care treatment, facilitating better resource allocation and patient management. In addition, we applied machine learning models to analyze the length of stay (LOS) of patients, an important factor which affects hospital resource needs, including bed availability. For this analysis, we have used a dataset covering hospital resources from different countries, which included details on the number of beds, MRI machines, and CT scanners over several years. We examined how technological advancements have influenced hospital resources and patient lenth of stay. Our findings indicated that improvements in technology have led to a reduction in patient length of stay over time. Notably this has uncovered valuable insights into the strong correlation between hospital beds and patient LOS, revealing hidden patterns that can inform future resource planning and management strategies. During our search for healthcare datasets, we encountered an important issue of maternal mortality and it remains a significant problem, particularly in developing countries and low-resource areas. Investigations in this process revealed that a lack of prper knowledge about maternal healthcare and safety measures contributes to high number of maternal and neonatal deaths. To address this, we explored a dataset containing information on blood sugar levels, blood pressure (both diastolic and systolic), body temperature, and other relevant metrics for pregnant women. We have predicted the risk levels which was categorized as low, medium, or high and identify high-risk cases early. By focusing on women at higher risk, we aimed to improve early interventions and reduce complications associated with maternal health. We have successfully concluded our thesis, summarizing the outcomes of all research conducted thus far. Additionally, we have explored the future potential of this work, discussing how the generalizability and performance of the developed models can be enhanced. This could be achieved by integrating more diverse, comprehensive, and real-time datasets in future efforts. PROF. NEETU GUPTA

2025-05-01T00:00:00Z Kumar, Naveen http://localhost:8080/xmlui/handle/123456789/6081 2026-04-21T06:51:03Z 2024-12-01T00:00:00Z

A Study of Non Classical Properties of Quantum States Manufactured by an Atom Field Interaction Kumar, Naveen This comprehensive theoretical study investigates quantum states generated via atomfield interactions, and their non-classical properties. The thesis includes nine chapters, each contributing valuable insights to our perception of quantum phenomena. The journey begins with an introduction in Chapter 1 that provides a brief overview of the research conducted during the specified period. Chapter 2 provides a comprehensive overview of prior research on quantum states generated through atom-field interactions, emphasizing their non-classical properties. This chapter highlights the significant contributions of various authors to the understanding and advancement of this domain. Chapter 3 outlines the systematic approach undertaken to investigate quantum states generated by atom-cavity field interactions and their non-classical properties. Following this, Chapter 4 explores the statistical analysis of the cavity field state manufactured by the interplay between atom and cavity field. It delves into understanding the behaviour of such system under the influence of an external driven field with a special focus on the statistical characteristics exhibited by the resulting cavity field state. The research primarily concerns to examine different statistical properties such as photon number distribution, Wigner function, Mandel’s Q parameter, and squeezing. Chapter 5 looks into a non-classical state generated by an atom-cavity field interaction in presence of a driven field. In the scheme, the two-level atom is moved through the cavity and driven by a classical field. The atom interacts dispersively with the cavity field which results in a photon-number-dependent Stark shift. Assuming that the atom enters the cavity in the excited state |a⟩, the output cavity field is taken into account. The state vector |ψ(t)⟩ describes the entire atom-field system but in our work, we deal with the statistical aspects of the cavity field only. The quantum state that corresponds to the output cavity field is obtained by tracing out the atom part from |ψ(t)⟩ ⟨ψ(t)|. Different quantum phase properties such as quantum phase distribution, angular Q phase function, phase dispersion are evaluated for the obtained radiation field. The second-order correlation function g 2 (0), an indirect phase characteristic, is also considered. Chapter 6 accomplishes the analysis of a non-classical state generated through the interaction between an atom and a single-mode electromagnetic cavity field. Using a nonlinear Hamiltonian approach, we have extended the conventional Jaynes-Cummings model by introducing non-linearity and deforming the field operators. The study focuses on exploring the system dynamics under these modifications. The main emphasis of this study is to analyze the statistical features displayed by the emerging cavity field state. This research delves into investigating iv statistical metrics like the distribution of photon numbers, Wigner function, Mandel’s Q parameter, squeezing properties, Qf function, and lower-order antibunching which are essential for understanding the quantum characteristics embedded into the dynamics of the cavity field system. In Chapter 7, we have investigated non-classical properties of a state generated by the interaction of a three-level atom with a quantized cavity field and an external classical driving field. In this study, the fields being degenerate in frequency, are highly detuned from the atom. The atom interacts with the quantized field in a dispersive manner. The experimental set-up involves a three-level atom passing through a cavity and interacting dispersively with the cavity field mode. Simultaneously, the atom interacts with an external classical field that is in resonance with the cavity field. The three-level atom can enter the cavity either in one of the bare states |e⟩, | f⟩ or |g⟩ or in a superposition of two of these states. We consider a superposition of |e⟩ and | f⟩. In our analysis, we have focused on the statistical properties of the cavity field after interacting with the atom. The state vector |ψ(t)⟩ describes the entire atom-field system but we have analyzed the properties of the cavity field independently after neglecting the atomic component of the system. For this, the atom part is traced out from |ψ(t)⟩ to acquire the cavity field state only, denoted by ψf(t) . We have evaluated different non-classical measures including photon number distribution, Mandel’s QM parameter, squeezing properties Sx and Sp, Wigner distribution, Qf function, and second-order correlation function g 2 (0) of the derived cavity field state. In Chapter 8, we have considered a system resulting from the interaction of two two-level atoms and a two-mode field inside an optical cavity that is embedded with a nonlinear Kerr-like medium. The study includes the effect of detuning parameter, Stark shift, atom-field coupling and third-order susceptibility of the Kerr medium on light intensity. We have obtained the exact solution of the Schrödinger equation after assuming that the atoms and the field are initially in superposition and coherent states, respectively. Our study aims to understand the dynamics of the system by finding out the exact analytical form of the state vector. Some statistical properties such as photon-number distribution, second-order correlation, Mandel’s QM and squeezing are investigated. Finally Chapter 9 offers a conclusive summary of the entire research work and outlines potential avenues for future exploration and investigation. The thesis collectively enriches our understanding of the non-classical features of different atom-field quantum states, paving the way for advancements in quantum information processing and technology DR. ARPITA CHATTERJEE

2024-12-01T00:00:00Z Kumar, Ajay http://localhost:8080/xmlui/handle/123456789/3404 2025-05-31T09:06:08Z 2023-12-01T00:00:00Z

Performance analysis of redundant systems with server failure under varying environment conditions Kumar, Ajay

2023-12-01T00:00:00Z