Photon sorters and QND detectors using single photon emitters

We discuss a new method for realizing number-resolving and non-demolition photo detectors by strong coupling of light to individual single photon emitters, which act as strong optical non-linearities. As a specific application we show how these elements can be integrated into an error-proof Bell state analyzer, whose efficiency exceeds the best possible performance with linear optics even for a modest atom-field coupling. The methods are error-proof in the sense that every detection event unambiguously projects the photon state onto a Fock or Bell state.Comment: revised and enlarged version, 6+ pages, 5 figure

Time reversal symmetry in optics

The utilization of time reversal symmetry in designing and implementing (quantum) optical experiments has become more and more frequent over the past years. We review the basic idea underlying time reversal methods, illustrate it with several examples and discuss a number of implications.Comment: 5 pages, 3 figures, typeset with revte

Aplikasi Macam Pupuk Organik Padat pada Padi Hibrida F2

Padi hibrida merupakan salah satu kunci untuk meningkatkan produksi beras dunia. Namun, benih padi hibrida hanya dapat digunakan untuk satu kali musim tanam, sehingga perlu adanya upaya yang harus dilakukan untuk mempertahankan produksi padi hibrida pada keturunan kedua (F2). Beberapa hal yang dapat dilakukan antara lain adalah dengan pemberian pupuk yang berimbang dan penerapan pengelolaan hara terpadu, salah satunya dengan penggunaan pupuk organik padat. Penelitian dilaksanakan di Desa Joho, Kecamatan Mojolaban, Kabupaten Sukoharjo pada bulan Januari hingga Juni 2016 dengan menggunakan rancangan penelitian Split Plot Rancangan Acak Kelompok Lengkap (RAKL) dengan 2 faktor perlakuan, yaitu macam pupuk organik padat dan varietas padi serta ulangan sebanyak 3 kali. Hasil penelitian menunjukkan bahwa perlakuan macam pupuk organik padat dan varietas padi memberikan pengaruh terhadap semua variabel pengamatan, kecuali pada variabel bobot 1000 butir gabah bernas dan hasil panen per petak

Quantifying the decay of quantum properties in single-mode states

The dissipative dynamics of Gaussian squeezed states (GSS) and coherent superposition states (CSS) are analytically obtained and compared. Time scales for sustaining different quantum properties such as squeezing, negativity of the Wigner function or photon number distribution are calculated. Some of these characteristic times also depend on initial conditions. For example, in the particular case of squeezing, we find that while the squeezing of CSS is only visible for small enough values of the field intensity, in GSS it is independent of this quantity, which may be experimentally advantageous. The asymptotic dynamics however is quite similar as revealed by the time evolution of the fidelity between states of the two classes.Comment: Accepted versio

Generation of a wave packet tailored to efficient free space excitation of a single atom

We demonstrate the generation of an optical dipole wave suitable for the process of efficiently coupling single quanta of light and matter in free space. We employ a parabolic mirror for the conversion of a transverse beam mode to a focused dipole wave and show the required spatial and temporal shaping of the mode incident onto the mirror. The results include a proof of principle correction of the parabolic mirror's aberrations. For the application of exciting an atom with a single photon pulse we demonstrate the creation of a suitable temporal pulse envelope. We infer coupling strengths of 89% and success probabilities of up to 87% for the application of exciting a single atom for the current experimental parameters.Comment: to be published in Europ. Phys. J.

Photon-Atom Coupling with Parabolic Mirrors

Efficient coupling of light to single atomic systems has gained considerable attention over the past decades. This development is driven by the continuous growth of quantum technologies. The efficient coupling of light and matter is an enabling technology for quantum information processing and quantum communication. And indeed, in recent years much progress has been made in this direction. But applications aside, the interaction of photons and atoms is a fundamental physics problem. There are various possibilities for making this interaction more efficient, among them the apparently 'natural' attempt of mode-matching the light field to the free-space emission pattern of the atomic system of interest. Here we will describe the necessary steps of implementing this mode-matching with the ultimate aim of reaching unit coupling efficiency. We describe the use of deep parabolic mirrors as the central optical element of a free-space coupling scheme, covering the preparation of suitable modes of the field incident onto these mirrors as well as the location of an atom at the mirror's focus. Furthermore, we establish a robust method for determining the efficiency of the photon-atom coupling.Comment: Book chapter in compilation "Engineering the Atom-Photon Interaction" published by Springer in 2015, edited by A. Predojevic and M. W. Mitchell, ISBN 9783319192307, http://www.springer.com/gp/book/9783319192307. Only change to version1: now with hyperlinks to arXiv eprints of other book chapters mentioned in this on

The CHSH-bell inequality and Tsirelson's bound with postselection

We show the necessary and sufficient conditions on loss for valid CHSH-Bell experiments, and propose an experiment with loss which should violate Tsirelson's bound for entangled states