Quantum control of electromagnetically induced transparency dispersion via atomic tunneling in a double-well Bose-Einstein condensate

Electromagnetically induced transparency (EIT) is an important tool for controlling light propagation and nonlinear wave mixing in atomic gases with potential applications ranging from quantum computing to table top tests of general relativity. Here we consider EIT in an atomic Bose-Einstein condensate (BEC) trapped in a double-well potential. A weak probe laser propagates through one of the wells and interacts with atoms in a three-level Lambda configuration. The well through which the probe propagates is dressed by a strong control laser with Rabi frequency Omega(mu), as in standard EIT systems. Tunneling between the wells at the frequency g provides a coherent coupling between identical electronic states in the two wells, which leads to the formation of interwell dressed states. The macroscopic interwell coherence of the BEC wave function results in the formation of two ultranarrow absorption resonances for the probe field that are inside of the ordinary EIT transparency window. We show that these new resonances can be interpreted in terms of the interwell dressed states and the formation of a type of dark state involving the control laser and the interwell tunneling. To either side of these ultranarrow resonances there is normal dispersion with very large slope controlled by g. We discuss prospects for observing these ultranarrow resonances and the corresponding regions of high dispersion experimentally.

The core characteristics and nursing care activities in psychiatric intensive care units in Sweden

Internationally, research on psychiatric intensive care units (PICUs) commonly reportsresults from demographic studies such as criteria for admission, need for involuntary treatment, andthe occurrence of violent behaviour. A few international studies describe the caring aspect of thePICUs based specifically on caregivers’ experiences. The concept of PICU in Sweden is not clearlydefined. The aim of this study is to describe the core characteristics of a PICU in Sweden and todescribe the care activities provided for patients admitted to the PICUs. Critical incident techniquewas used as the research method. Eighteen caregivers at a PICU participated in the study bycompleting a semistructured questionnaire. In-depth interviews with three nurses and two assistantnurses also constitute the data. An analysis of the content identified four categories that characterizethe core of PICU: the dramatic admission, protests and refusal of treatment, escalating behaviours, andtemporarily coercive measure. Care activities for PICUs were also analysed and identified as controlling– establishing boundaries, protecting – warding off, supporting – giving intensive assistance, andstructuring the environment. Finally, the discussion put focus on determining the intensive aspect ofpsychiatric care which has not been done in a Swedish perspective before. PICUs were interpreted asa level of care as it is composed by limited structures and closeness in care.

Parent’s experiences of feeding their preterm infant in Neonatal Units in Sweden. : Ethnographic design

Introduction: Studies have shown that having a preterm infant may cause stress and powerlessness for parents. It is important to support parents around the feeding situation, and that the Neonatal Intensive Care Unit (NICU) has appropriate space and place to help the family to bond to each other. For the healthcare professionals it is important to promote skin-to-skin contact and breastfeeding; particularly for preterm infants. There are many studies on parent’s experiences of NICUs and a few studies on parent’s experiences of feeding their infant in the NICU. Objective: The objective of this study was to explore parents experiences of feeding their infant in the NICU. Design: The study was conducted using an ethnographic design. Results: A global theme of ‘The journey in feeding’ was developed from four organising themes: ‘Ways of infant feeding’; ‘Environmental influences’; ‘Relationships’ and ‘Emotional factors’. These themes illustrate the challenges mothers reported with different methods of feeding. The environment had a big impact on parent’s experiences of infant feeding. Some mothers felt that breastfeeding seemed unnatural because their infant was so tiny but breastfeeding and skin-to-skin contact helped them to bond to their infant. The mothers thought it was difficult to keep up with the milk production by only pumping. Routines were not inviting parents to find their own rhythm. They also felt stressed about the weighing. Healthcare professionals had positive and negative influences on the parents. Conclusions: This study demonstrates that while all parents expressed the wish to breastfeed, their ‘journey in feeding’ was highly influenced by method of feeding, environmental, relational and emotional factors. The general focus upon routines and assessing milk intake generated anxiety and reduced relationality. Midwives and neonatal nurses need to ensure that they emphasise and support the relational aspects of parenting and avoid over-emphasising milk intake and associated progress of the infant