arXiv subjects

Aline Medina

Publications and source records attributed to Aline Medina.

3 recordsLinked to original sources

arXiv2020

Quantum State Preparation of Hydrogen Atoms by Hyperfine Quenching

We discuss the use of a region of uniform and constant magnetic field in order to implement a two-state atomic polarizer for an H(2S) beam. We have observed that a device with such field configuration is capable of achieving an efficient polarization for a wide range of magnetic field intensities and atomic velocities. In addition, we establish a criterion that must be met to confirm a successful polarization. That is possible due to a specific beating pattern for the Lyman-$α$ radiation expected for the outgoing two-state atomic beam.

physics.atom-ph↗

arXiv2015

Toward a test of angular momentum coherence in a twin-atom interferometer

We present a scheme well-suited to investigate quantitatively the angular momentum coherence of molecular fragments. Assuming that the dissociated molecule has a null total angular momentum, we investigate the propagation of the corresponding atomic fragments in the apparatus. We show that the envisioned interferometer enables one to distinguish unambiguously a spin-coherent from a spin-incoherent dissociation, as well as to estimate the purity of the angular momentum density matrix associated with the fragments. This setup, which may be seen as an atomic analogue of a twin-photon interferometer, can be used to investigate the suitability of molecule dissociation processes -- such as the metastable hydrogen atoms H($2^2 S$)-H($2^2 S$) dissociation - for coherent twin-atom optics.

quant-ph↗

arXiv2013

Experimental evidence of twin fast metastable H(2S) atoms from dissociation of cold H_2 induced by electrons

We report the direct detection of two metastable H(2S) atoms coming from the dissociation of a single cold H_2 molecule, in coincidence measurements. The molecular dissociation was induced by electron impact in order to avoid limitations by the selection rules governing radiative transitions. Two detectors, placed close from the collision center, measure the neutral metastable H(2S) through a localized quenching process, which mixes the H(2S) state with the H(2P), leading to a Lyman-αdetection. Our data show the accomplishment of a coincidence measurement which proves for the first time the existence of the H(2S)-H(2S) dissociation channel.

physics.atom-ph↗