We present the measurement results of the pre-flight characterization and calibration of the EnMAP HyperSpectral Imager (HSI) and draw conclusions on the performance of the instrument itself as well as the optical ground support equipment (OGSE) deployed.The HSI is capable of measuring the solar irradiance reflected from the Earth's surface as a continuous spectrum in the spectral range of 420 nm to 2450 nm, with an average spectral sampling of 6.5nm (VNIR) and 10nm (SWIR).The EnMAP swath of 30 km is sampled with 30 m in along and across track direction.The on-ground characterization was performed in air comprising a spectral, geometric, radiometric, polarimetric, and stray light characterization.For spectral calibration, a monochromator setup was used to characterize the spectral response function of the instrument yielding a wavelength and spectral resolution calibration including spectral smile.Geometric calibration was performed using a knife edge in the focal plane of a collimator allowing to determine the line of sight of each pixel.Additionally, the keystone and MTF performance of the instrument was confirmed.A large integrating sphere was used for radiometric characterization of the instrument.This provides an on-ground baseline calibration of radiometric coefficients and response non-uniformity to be updated in orbit.Additionally, the noise performance of the instrument was validated.A polarizer was used to measure polarization sensitivity of the instrument which was found to be in excellent agreement with expectations.Finally a stray light characterization of the instrument was conducted.

The Environmental Mapping and Analysis Program HyperSpectral Imager (EnMAP HSI) will allow to acquire images of the Earth surface in a push-broom configuration. Spectral coverage includes 230 wavelength bands between 420 nm and 2450 nm, which are simultaneously recorded with a ground resolution of 30 m x 30 m. High requirements on the optical alignment of the Visual Near InfraRed (VNIR) and Short Wavelength InfraRed (SWIR) spectrometers and cameras have been fulfilled (one pixel lateral alignment and below 20 μm for defocus). In addition, a calibration and characterization campaign of the EnMAP HSI was performed, with the aim to verify the instrument requirements and to quantify its performance. The campaign addressed the following five responsivity domains: radiometric, polarization, spectral responsivity, spatial responsivity and stray light. A spectral calibration accuracy of 0.5 nm for VNIR and 1 nm for SWIR channel, and lateral calibration of the full field-of-view with sub-arc second accuracy was achieved. For all measurements, traceability to national standards is guaranteed by comparative measurements with calibrated devices. The paper presents the setups of the alignment, calibration and characterization measurements of the EnMAP HSI. Instrument requirements on calibration accuracy are reported. The traceability to national standards will be described and the validation of measurement accuracy.

The EnMAP hyperspectral Imager (HSI)1 will allow to acquire Images of the Earth surface in a push broom configuration. 230 wavelength bands between 420nm and 2450nm are simultaneously recorded with a ground resolution of 30m x 30m. The entire satellite is designed and built by OHB-Systems. Characterizing and calibrating a state-of-the-art hyperspectral instrument as the EnMAP HSI requires to establish measurement setups that outperform the test object in all relevant performance aspects to achieve the required measurement accuracies. At the same time technical as well as economical considerations yield to develop measurement equipment that can support multiple use cases throughout the Alignment integration and Test (AIT) Process of the Instrument. This paper reports on development and commissioning activities of optical ground support equipment (OGSE) for full aperture testing of the EnMAP HSI. Design requirements as well as measured setup performance is reported. The overall OGSE-system has been set-up and commissioned at OHB in Oberpfaffenhofen. It supports the following measurement cases: • Double-pass wave front measurement of the HSI-Telescope for alignment to the HSI-Spectrometer Module • Line of sight characterisation of the HSI with sub-arcsecond accuracy • Scanning knife edge modulation transfer function (MTF)-Measurement of the HSI in the entire field-of-view • Spectral response characterisation of the HSI in the entire spectral range with sub-nanometer wavelength accuracy. The OGSE consists of several modules. The core component, a highly stable diffraction-limited 200 mm Collimator including a movement system and a scene generator was designed and built by Bertin Technologies upon OHB specifications.

The Environmental Mapping and Analysis Program (EnMAP) is a German space borne science mission that aims to characterize the Earth’s environment on a global scale. The single payload of the satellite is the Hyperspectral Imager (HSI). It is capable of measuring the solar irradiance reflected from the Earth’s surface as a continuous spectrum in the spectral range of 420nm to 2450nm, with an average spectral sampling of 6.5nm (VNIR) and 10nm (SWIR). The EnMAP swath of 30km is sampled with 30m in along and across track direction. In these proceedings, we first give a brief overview the instrument design. We then explain the calibration strategy, which is a combination of on-ground and in-flight calibration measures. The on-ground calibration is presented in more detail. It aims to create a complete baseline calibration of the EnMAP instrument comprising a radiometric, spectral, geometric, polarimetric and straylight characterization. In orbit, a diffuser is used for absolute radiometric calibration via sun viewing. On-board calibration light sources ensure radiometric stability in between sun-viewings and spectral stability over the mission lifetime. Finally, we share first characterization data which are prototypical of the final instrument calibration.

The EnMAP telescope is an off-axis telescope made of three aspherical mirrors and a folding mirror mounted on bipods. Following a highly precise mechanical placement process [1], final alignment is performed by position correction of a single compensator element. The mirror position change by shimming is demonstrated to be reproducible within 1 μm.

The Environmental Mapping and Analysis Program (EnMAP) is a German hyperspectral mission with pushbroom type imaging spectrometers covering the wavelength ranges from 420 nm to 2450 nm. The ground sampling distance is 30 m with a total swath of 30 km, while the spectral sampling distance is roughly 5 nm to 12 nm.

A scheme based on electromagnetically induced transparency is used to store light in a Bose-Einstein condensate. In this process, a photonic polarization qubit is stored in atomic Zeeman states. The performance of the storage process is characterized and optimized. The average process fidelity is 1.000 +/- 0.004. For long storage times, temporal fluctuations of the magnetic field reduce this value, yielding a lifetime of the fidelity of (1.1 +/- 0.2) ms. The write-read efficiency of the pulse energy can reach 0.53 +/- 0.05.

Entanglement between stationary systems at remote locations is a key resource for quantum networks. We report on the experimental generation of remote entanglement between a single atom inside an optical cavity and a Bose-Einstein condensate (BEC). To produce this, a single photon is created in the atom-cavity system, thereby generating atom-photon entanglement. The photon is transported to the BEC and converted into a collective excitation in the BEC, thus establishing matter-matter entanglement. After a variable delay, this entanglement is converted into photon-photon entanglement. The matter-matter entanglement lifetime of 100 μs exceeds the photon duration by 2 orders of magnitude. The total fidelity of all concatenated operations is 95%. This hybrid system opens up promising perspectives in the field of quantum information.

Geometric phase phenomena in single neutrons have been observed in polarimeter and interferometer experiments. Interacting with static and time dependent magnetic fields, the state vectors acquire a geometric phase tied to the evolution within spin subspace. In a polarimeter experiment the non-additivity of quantum phases for mixed spin input states is observed. In a Si perfect-crystal interferometer experiment appearance of geometric phases, induced by interaction with an oscillating magnetic field, is verified. The total system is characterized by an entangled state, consisting of neutron and radiation fields, governed by a Jaynes-Cummings Hamiltonian. In addition, the influence of the geometric phase on a Bell measurement, expressed by the Clauser-Horne-Shimony-Holt (CHSH) inequality, is studied. It is demonstrated that the effect of geometric phase can be balanced by an appropriate change of Bell angles.

The strength of interparticle interactions in cold gases can be tuned using magnetic fields. This widely used approach is now combined with laser manipulation, providing additional flexibility, such as the possibility of spatially modulating the interaction strength on short length scales. The capability to tune the strength of the elastic interparticle interaction is crucial for many experiments with ultracold gases. Magnetic Feshbach resonances1,2 are widely harnessed for this purpose, but future experiments3,4,5,6,7,8 would benefit from extra flexibility, in particular from the capability to spatially modulate the interaction strength on short length scales. Optical Feshbach resonances9,10,11,12,13,14,15 do offer this possibility in principle, but in alkali atoms they induce rapid loss of particles due to light-induced inelastic collisions. Here, we report experiments that demonstrate that light near-resonant with a molecular bound-to-bound transition in 87Rb can be used to shift the magnetic field at which a magnetic Feshbach resonance occurs. This enables us to tune the interaction strength with laser light, but with considerably less loss than using an optical Feshbach resonance.

In a neutron polarimetry experiment mixed neutron spin phases are determined. We consider evolutions leading to purely geometric, purely dynamical and combined phases. It is experimentally demonstrated that the sum of the geometric and dynamical phases - both obtained in separate measurements - is not equal to the associated total phase as obtained from a third measurement, unless the system is in a pure state. In this sense, mixed state phases are not additive.

We show that strong inelastic interactions between bosons in one dimension create a Tonks-Girardeau gas, much as in the case of elastic interactions. We derive a Markovian master equation that describes the loss caused by the inelastic collisions. This yields a loss rate equation and a dissipative Lieb-Liniger model for short times. We obtain an analytic expression for the pair correlation function in the limit of strong dissipation. Numerical calculations show how a diverging dissipation strength leads to a vanishing of the actual loss rate and renders an additional elastic part of the interaction irrelevant.

Strongly correlated states in many-body systems are traditionally created using elastic interparticle interactions. Here we show that inelastic interactions between particles can also drive a system into the strongly correlated regime. This is shown by an experimental realization of a specific strongly correlated system, namely a one-dimensional molecular Tonks-Girardeau gas.

We present a theoretical investigation of a lattice Tonks–Girardeau gas that is created by inelastic, instead of elastic interactions. An analytical calculation shows that in the limit of strong two-body losses, the dynamics of the system is effectively that of a hard-core boson gas. We also derive an analytic expression for the effective loss rate. We find good agreement between these analytical results and results from a rigorous numerical calculation. The hard-core character of the particles is visible both in a reduced effective loss rate and in the momentum distribution of the gas.

We use laser light near resonant with an optical bound-to-bound transition to shift the magnetic field at which a Feshbach resonance occurs. We operate in a regime of large detuning and large laser intensity. This reduces the light-induced atom-loss rate by 1 order of magnitude compared to our previous experiments [D. M. Bauer , Nat. Phys. 5, 339 (2009)]. The experiments are performed in an optical lattice and include high-resolution spectroscopy of excited molecular states reported here. In addition, we give a detailed account of a theoretical model that describes our experimental data.

In a neutron polarimetry experiment the mixed-state relative phases between spin eigenstates are determined from the maxima and minima of measured intensity oscillations. We consider evolutions leading to purely geometric, purely dynamical, and combined phases. It is experimentally demonstrated that the sum of the individually determined geometric and dynamical phases is not equal to the associated total phase which is obtained from a single measurement, unless the system is in a pure state.

Atomic quantum gases in the strong-correlation regime offer unique possibilities to explore a variety of many-body quantum phenomena. Reaching this regime has usually required both strong elastic and weak inelastic interactions because the latter produce losses. We show that strong inelastic collisions can actually inhibit particle losses and drive a system into a strongly correlated regime. Studying the dynamics of ultracold molecules in an optical lattice confined to one dimension, we show that the particle loss rate is reduced by a factor of 10. Adding a lattice along the one dimension increases the reduction to a factor of 2000. Our results open the possibility to observe exotic quantum many-body phenomena with systems that suffer from strong inelastic collisions.

We observe large-amplitude Rabi oscillations between an atomic and a molecular state near a Feshbach resonance. The experiment uses 87Rb in an optical lattice and a Feshbach resonance near 414 G. The frequency and amplitude of the oscillations depend on the magnetic field in a way that is well described by a two-level model. The observed density dependence of the oscillation frequency agrees with theoretical expectations. We confirmed that the state produced after a half-cycle contains exactly one molecule at each lattice site. In addition, we show that, for energies in a gap of the lattice band structure, the molecules cannot dissociate.