STRUKTUR KOMUNITAS TUMBUHAN PANTAI DI GILI LABAK KABUPATEN SUMENEP SEBAGAI SUMBER BELAJAR BIOLOGI

Gili Labak is an island by its enticing natural potency. It makes this island as tourist destination in order that it increases local or regional tourists and creates new economic resources. Therefore, due to the reason, it also creates tensions toward environment and coastal ecosystems that affect the structure of plant communities there. This study aims to know variety of plants species, evenness, relative abundance, important value index (IVI) and result of the study as learning source of biology. Additionally, the study used quantitative approach by descriptive research design. Furthermore, the sample of the study is all of coastal plants in Gili Labak which is in the plot. The result of the study represented the highest variety of plants species in Gili Labak coast are found in station 2 (no tourism facilities) with value of 501,15 and more than station 1 (tourism facilities provided) with value of 451,64, by the highest evenness of plants in Gili Labak coast of Sumenep Regency is founded in station 1 (tourism facilities provided) namely Leucaena leucocephala, relative abundance is greatly influenced by physical condition of environment such as air temperature, soil temperature, soil pH and soil texture. Then, the highest IVI of structure of plant communities in Gili Labak coast of Sumenep Regency is Leucaena leucocephala with value 0,85% in station 1 (tourism facilities provided) and 0,87% in station 2 (no tourism facilities). The study of Structure of Plant Communities could be used as learning sources of Biology of Junior High School on “Environmental Changes” subject and as lab modules of Senior High School of X grade on the subject of “Ecology”

Magnetic trapping and coherent control of laser-cooled molecules

We demonstrate coherent microwave control of the rotational, hyperfine and Zeeman states of ultracold CaF molecules, and the magnetic trapping of these molecules in a single, selectable quantum state. We trap about 5 X 10³ molecules for almost 2s at a temperature of 70(8) μK and a density of 1.2 X 10⁵ cm⁻³. We measure the state-specific loss rate due to collisions with background helium

A buffer gas beam source for short, intense and slow molecular pulses

Experiments with cold molecules usually begin with a molecular source. We describe the construction and characteristics of a cryogenic buff er gas source of CaF molecules. The source emits pulses with a typical duration of 240 μs, a mean speed of about 150 m/s, and a flux of 5x 10¹⁰ molecules per steradian per pulse in a single rotational state

New techniques for a measurement of the electron's electric dipole moment

The electric dipole moment of the electron (eEDM) can be measured with high precision using heavy polar molecules. In this paper, we report on a series of new techniques that have improved the statistical sensitivity of the YbF eEDM experiment. We increase the number of molecules participating in the experiment by an order of magnitude using a carefully designed optical pumping scheme. We also increase the detection efficiency of these molecules by another order of magnitude using an optical cycling scheme. In addition, we show how to destabilise dark states and reduce backgrounds that otherwise limit the efficiency of these techniques. Together, these improvements allow us to demonstrate a statistical sensitivity of 1.8 x 10⁻²⁸ e cm after one day of measurement, which is 1.2 times the shot-noise limit. The techniques presented here are applicable to other high-precision measurements using molecules

Molecules cooled below the Doppler limit

The ability to cool atoms below the Doppler limit -- the minimum temperature reachable by Doppler cooling -- has been essential to most experiments with quantum degenerate gases, optical lattices and atomic fountains, among many other applications. A broad set of new applications await ultracold molecules, and the extension of laser cooling to molecules has begun. A molecular magneto-optical trap has been demonstrated, where molecules approached the Doppler limit. However, the sub-Doppler temperatures required for most applications have not yet been reached. Here we cool molecules to 50 uK, well below the Doppler limit, using a three-dimensional optical molasses. These ultracold molecules could be loaded into optical tweezers to trap arbitrary arrays for quantum simulation, launched into a molecular fountain for testing fundamental physics, and used to study ultracold collisions and ultracold chemistry

Measuring the stability of fundamental constants with a network of clocks

The detection of variations of fundamental constants of the Standard Model would provide us with compelling evidence of new physics, and could lift the veil on the nature of dark matter and dark energy. In this work, we discuss how a network of atomic and molecular clocks can be used to look for such variations with unprecedented sensitivity over a wide range of time scales. This is precisely the goal of the recently launched QSNET project: A network of clocks for measuring the stability of fundamental constants. QSNET will include state-of-the-art atomic clocks, but will also develop next-generation molecular and highly charged ion clocks with enhanced sensitivity to variations of fundamental constants. We describe the technological and scientific aims of QSNET and evaluate its expected performance. We show that in the range of parameters probed by QSNET, either we will discover new physics, or we will impose new constraints on violations of fundamental symmetries and a range of theories beyond the Standard Model, including dark matter and dark energy models

Enhancing dipolar interactions between molecules using state-dependent optical tweezer traps

We show how state-dependent optical potentials can be used to trap a pair of molecules in different internal states at a separation much smaller than the wavelength of the trapping light. This close spacing greatly enhances the dipole-dipole interaction and we show how it can be used to implement two-qubit gates between molecules that are 100 times faster than existing protocols and than rotational coherence times already demonstrated. We analyze complications due to hyperfine structure, tensor light shifts, photon scattering and collisional loss, and conclude that none is a barrier to implementing the scheme

Laser cooling of molecules

Recently, laser cooling methods have been extended from atoms to molecules. The complex rotational and vibrational energy level structure of molecules makes laser cooling difficult, but these difficulties have been overcome and molecules have now been cooled to a few microkelvin and trapped for several seconds. This opens many possibilities for applications in quantum science and technology, controlled chemistry, and tests of fundamental physics. This article explains how molecules can be decelerated, cooled and trapped using laser light, reviews the progress made in recent years, and outlines some future applications