Beam splitting and Hong-Ou-Mandel interference for stored light

Storing and release of a quantum light pulse in a medium of atoms in the tripod configuration are studied. Two complementary sets of control fields are defined, which lead to independent and complete photon release at two stages. The system constitutes a new kind of a flexible beam splitter in which the input and output ports concern photons of the same direction but well separated in time. A new version of Hong-Ou-Mandel interference is discussed.Comment: 8 pages, 3 figure

Electromagnetically-induced transparency and light storing of a pair of pulses

Electromagnetically-induced transparency and light storing are studied in the case of a medium of atoms in a double Lambda configuration, both in terms of dark- and bright-state polatitons and atomic susceptibility. It is proven that the medium can be made transparent simultaneously for two pulses following their self-adjusting so that a condition for an adiabatic evolution has become fulfilled. Analytic formulas are given for the shapes and phases of the transmitted/stored pulses. The level of transparency can be regulated by adjusting the heights and phases of the control fields.Comment: text +6 figure

Coherent processing of a light pulse stored in a medium of four-level atoms

It is demonstrated that the properties of light stored in a four-level atomic system can be modified by an additional control interaction present during the storage stage. By choosing the pulse area of this interaction one can in particular continuously switch between two channels into which light is released.Comment: text+4 figure

Light slowdown in the vicinity of cross-over resonances

Pulse propagation is considered in an inhomogeneously broadened medium of three-level atoms in a V-configuration, dressed by a counter-propagating pump pulse. A significant signal slowdown is demonstrated in this of the three frequency windows of a reduced absorption and a steep normal dispersion, which is due to a cross-over resonance. Particular properties of the group index in the vicinity of such a resonance are demonstrated in the case of closely spaced upper levels.Comment: 4 figure

Controlling statistical properties of stored light

Statistical properties of outgoing light pulses are studies after they have been stored in a medium of atoms in the tripod configuration. A generalized Hong-Ou-Mandel interference, storing of squeezed states and homodyne signal analysis are discussed in the context of their dependence on the parameters of the control fields used for light storage and release.Comment: 5 figure

Suppressing Recoil Heating in Levitated Optomechanics using Squeezed Light

We theoretically show that laser recoil heating in free-space levitated optomechanics can be arbitrarily suppressed by shining squeezed light onto an optically trapped nanoparticle. The presence of squeezing modifies the quantum electrodynamical light-matter interaction in a way that enables us to control the amount of information that the scattered light carries about a given mechanical degree of freedom. Moreover, we analyze the trade-off between measurement imprecision and back-action noise and show that optical detection beyond the standard quantum limit can be achieved. We predict that, with state-of-the-art squeezed light sources, laser recoil heating can be reduced by at least 60% by squeezing a single Gaussian mode with an appropriate incidence direction, and by 98% by squeezing a properly mode-matched mode. Our results, which are valid both for motional and librational degrees of freedom, will lead to improved feedback cooling schemes as well as boost the coherence time of optically levitated nanoparticles in the quantum regime.Comment: 16 pages, 5 figure

The evaluation of the quality of life in patients’ families during terminal malignancy at home

Wstęp. Okres terminalny to okres, gdy wyczerpały się możliwości dalszego przedłużania życia osoby przewlekle chorej bezpośrednim oddziaływaniem na przyczynę choroby, a chory wy-maga objęcia go opieką. Rodzina spotyka się wówczas z szeregiem problemów, w tym także ze zmianami swojej jakości życia. Problemy te rzadko poruszane w literaturze tematu skłoniły autorów do podjęcia badań własnych. Celem badań była ocena jakości życia członków rodzin pacjentów w terminalnym okresie choroby nowotworowej w warunkach domowych. Materiał i metody. Przebadano 60 osób – członków rodzin i jednocześnie opiekunów pacjentów będących w terminalnym okresie choroby nowotworowej, przebywających w domu. Sondaż został prze-prowadzony samodzielnie z uwzględnieniem wymagań etycznych tj. badanych poinformowano o anonimowości i celu przeprowadzonej ankiety. Pytania w nim zawarte dotyczyły sfery biopsycho-społecznej ankietowanych. Wyniki i wnioski. Jakość życia opiekunów chorych terminalnych obniża się. Pogorszenie jakości życia następuje zwłaszcza wtedy, gdy sprawowanie opieki spada na jedną osobę. Łączenie opieki z obowiązkami prowadzenia domu i pracy zawodowej, udzielanie wsparcia psychicznego choremu z jednoczesnym przeżywaniem perspektywy rozstania, rodzi uczucie przygnębienia i smutku. Także u chorego wywołuje to negatywne emocje np. drażliwość, gniew, depresję. Choroba w rodzinie wpływa na sytuację społeczno – zawodową badanych. 33,3% zmieniła całkowicie plany życiowe, co wiązało się z decyzją o zmniejszeniu czasu pracy i rezygnacji z dotychczasowego sposobu spędzania wolnego czasu. U respondentów, u których stwierdza się obniżenie jakości życia pomoc powinna obejmować sfery psychologiczno – bytowe rodziny. Sprawą podstawową byłoby podjęcie prób poprawy komunikacji i kontaktów wzajemnych z rodziną i poradnictwo psychologiczne. Równie ważna staje się opieka medyczna, nauka opiekunów zasad pielęgnacji, wiedza na temat możliwych nowych objawów chorobowych. Kolosalne znaczenie ma uświadomienie rodzinie, że choroba w fazie terminalnej jest nieodwracalną, nieuchronnie prowadzącą do śmierci.Introduction. Terminal malignancy is a period when the possibilities of prolonging a chronically ill patient’s life by means of affecting the cause of the disease are gone, and the patient is in need of care. Families encounter a lot of problems then, some of them related to the change in their quality of life. As these problems are infrequently undertaken in the literature of the field, the authors decided to conduct their own research. The purpose of it was to evaluate the quality of life of patients’ families during terminal malignancy at home. Materials and methods. 60 people were examined – they were all relatives and at the same time carers of terminal malignancy patients residing at their houses. The survey was conducted by authors them selves with a special consideration given to the ethical regulations, i.e. informing the interviewed about their anonymity and the purpose of the survey. The questions included in it were biological, psychological and social in nature. Results and conclusion. The quality of life is declining for carers of the terminally ill. The decline is the case especially when there is only one person to handle the related responsibilities. The care over the patient conjoined with running the household and professional life as well as supporting the patient while bearing the prospect of parting in mind are the sources of sadness and depression. Patients experience negative emotions as well, for instance irritation, anger, depression. The illness in a family affects the socio-professional situation of its members. 33,3% of them change their life plans entirely, which included decreasing the work frequency and giving up the previous leisure activities. The help offered to the respondents who experienced a decline in their quality of life should be psychological and existential. A basic issue here would be an attempt to make amends to the mutual communication and relations in the family as well as psychological counselling. Equally important is medical care as well as teaching the carers how to tend the sick person and what new symptoms may occur. Making it clear to the family that the terminal illness is irreversible and always leads to death is of utter importance