Three-level Dicke quantum battery

Quantum battery (QB) is the energy storage and extraction device that is governed by the principles of quantum mechanics. Here we propose a three-level Dicke QB and investigate its charging process by considering three quantum optical states: a Fock state, a coherent state, and a squeezed state. The performance of the QB in a coherent state is substantially improved compared to a Fock and squeezed states. We find that the locked energy is positively related to the entanglement between the charger and the battery, and diminishing the entanglement leads to the enhancement of the ergotropy. We demonstrate the QB system is asymptotically free as $N \rightarrow \infty$. The stored energy becomes fully extractable when $N=10$, and the charging power follows the consistent behavior as the stored energy, independent of the initial state of the charger.Comment: 9 Pages, 9 Figure

Exploration of the use of complementary approaches to end-of-life care: the perspectives and work of hospice palliative Buddhist chaplains in Taiwan

This study was motivated by the researcher’s experience of working in end-of-life care and by the literature review which revealed a gap in the knowledge and understanding of the role of religious methods as complementary approaches in managing the experience of living with a life-limiting illness in Taiwan. Trans-cultural issues are extremely important to end-of-life care. In Taiwan, patients approaching death have used religious methods as complementary approaches to manage the experience of living with a life-limiting illness, and religious belief systems shape patients’ understandings of what is happening. Current literature coupled with the experience of palliative care personnel identified that some patients with religious persuasions were refusing western medical treatments when they recognised that they were in the end stage of disease because they believed that these treatments could not control death and rebirth. However, few studies have discussed this experience and its meaning. Buddhist chaplains, as providers of supportive palliative care services through therapeutic care, have presented their understanding of the way that people move towards death and dying in Buddhist temples, universities, and in public speeches, but not often in hospitals. Buddhist chaplains’ life experience and interpretations influence the thinking processes and decision-making of many of those they come in contact with, especially those who share the Buddhist faith. However, few studies have demonstrated the way in which patients have made use of religious methods as complementary approaches from the perspective of hospice palliative Buddhist chaplains. The perspectives and work of hospice palliative Buddhist chaplains regarding “hospice palliative care” and patients’ use of religious methods as complementary approaches in end-of-life care in Taiwan were explored. The research questions were: (1) How do the Buddhist chaplains define “hospice palliative care”? (2) How do Buddhist chaplains use Buddhist religious methods as complementary approaches in clinical end-of-life care? (3) What are the experiences of Buddhist chaplains regarding the patients’ use of Buddhist religious methods as complementary approaches in clinical end-of-life care? (4) What are the opinions of Buddhist chaplains regarding patients’ use of Buddhist religious methods as complementary approaches in clinical end-of-life care? Charmaz’s (2006) constructivist grounded theory method was adopted. Data collection used triangulation and included demographic questionnaires, semi-structured face-to-face interviews, field notes, and written memos. Purposive sampling was used to recruit participants with rich working experiences in clinical end-of-life care. Twenty female and two male Buddhist chaplains aged between 33 and 67 years old participated. Charmaz’s (2006) constructivist grounded theory, which included comparative method, and three analytical phases (initial coding, focused coding and theoretical coding) informed the data analysis. The findings demonstrate that Buddhist concepts of death, the process of dying, and the ethics and tools of the Buddhist religion formed the basis of the practice of the chaplains who regarded compassionate care and Mahayana Buddhism as the main content of Buddha’s teachings. All participants used aspects of Buddhist philosophy to define “hospice palliative care”. The final theoretical framework emerged from the data to provide a structure to interpret “the dynamic process of compassionate care”. Compassionate care is a multifaceted, dynamic phenomenon practised by the chaplains. Mahayana Buddhism provides the specific tools through which they interacted with patients creating a sacred relationship that allowed patients to understand their context and cope with their end-of-life experiences. The thesis concluded that Buddhist chaplains’ understanding of compassionate care was influenced by their educational background, hospice training courses, and Buddha’s teachings to enable them to play important roles in end-of-life care in Taiwan. Recommendations are made for future studies to test the theoretical framework regarding “the dynamic process of compassionate care” with different professional staff such as nurses, psychologists and mental health physicians. The findings are also relevant for future government policy concerning the financial cost of end-of-life care which is currently provided by Buddhist chaplains from a Charity rather than by Taiwanese National Health Insurance. Finally it recommends that the findings inform the future education of medical and nursing students and staff in hospice end-of-life care in Taiwan

Entanglement witness and entropy uncertainty of open Quantum systems under Zeno effect

The entanglement witness and the entropy uncertainty are investigated by using the pseudomode theory for the open two-atom system under the quantum Zeno effect. The results show that, only when the two spectrums satisfy strong coupling with the atom, the time of entanglement witness can be prolonged and the lower bound of the entropic uncertainty can be reduced, and the entanglement can be witnessed many times. We also gave the corresponding physical explanation by the non-Markovianity. The Zeno effect not only can very effectively prolong the time of entanglement witness and reduce the lower bound of the entropy uncertainty, but also can greatly enhance the time of entanglement witness and reduce the entanglement value of witness