arXiv subjects

Harald Kübler

Publications and source records attributed to Harald Kübler.

24 records · Page 2Linked to original sources

arXiv2016

RF-dressed Rydberg atoms in hollow-core fibres

The giant electro-optical response of Rydberg atoms manifests itself in the emergence of sidebands in the Rydberg excitation spectrum if the atom is exposed to a radio-frequency (RF) electric field. Here we report on the study of RF-dressed Rydberg atoms inside hollow-core photonic crystal fibres (HC-PCF), a system that enables the use of low modulation voltages and offers the prospect of miniaturised vapour-based electro-optical devices. Narrow spectroscopic features caused by the RF field are observed for modulation frequencies up to 500 MHz.

physics.atom-ph↗

arXiv2015

Atomic vapor spectroscopy in integrated photonic structures

We investigate an integrated optical chip immersed in atomic vapor providing several waveguide geometries for spectroscopy applications. The narrow-band transmission through a silicon nitride waveguide and interferometer is altered when the guided light is coupled to a vapor of rubidium atoms via the evanescent tail of the waveguide mode. We use grating couplers to couple between the waveguide mode and the radiating wave, which allow for addressing arbitrary coupling positions on the chip surface. The evanescent atom-light interaction can be numerically simulated and shows excellent agreement with our experimental data. This work demonstrates a next step towards miniaturization and integration of alkali atom spectroscopy and provides a platform for further fundamental studies of complex waveguide structures.

physics.atom-ph↗

arXiv2014

Triple stack glass-to-glass anodic bonding for optogalvanic spectroscopy cells with electrical feedthroughs

We demonstrate the use of an anodic bonding technique for building a vacuum tight vapor cell for the use of Rydberg spectroscopy of alkali atoms with thin film electrodes on the inside of the cell. The cell is fabricated by simultaneous triple stack glass-to-glass anodic bonding at 300°C. This glue-free, low temperature sealing technique provides the opportunity to include thin film electric feedthroughs. The pressure broadening is only limited by the vapor pressure of rubidium and the lifetime is at least four months with operating temperatures up to 230°C.

physics.atom-ph↗

arXiv2013

Atom Based Vector Microwave Electrometry Using Rubidium Rydberg Atoms in a Vapor Cell

It is clearly important to pursue atomic standards for quantities like electromagnetic fields, time, length and gravity. We have recently shown, using Rydberg states, that Rb atoms in a vapor cell can serve as a practical, compact standard for microwave electric field strength. Here, we demonstrate, for the first time, that Rb atoms excited in a vapor cell can also be used for vector microwave electrometry by using Rydberg atom electromagnetically induced transparency. We describe the measurements necessary to obtain an arbitrary microwave electric field polarization at a resolution of $0.5^\circ$. The experiments are compared to theory and found to be in excellent agreement.

physics.atom-ph↗

arXiv2012

Fabrication and characterization of an electrically contacted vapor cell

We demonstrate the use of electrically contacted vapor cells to switch the transmission of a probe laser. The excitation scheme makes use of electromagnetically induced transparency involving a Rydberg state. The cell fabrication technique involves thinfilm based electric feedthroughs which are well suited for scaling this concept to many addressable pixels like in flat panel displays.

physics.atom-ph↗

arXiv2007

Electromagnetically Induced Transparency in optically trapped rubidium atoms

We demonstrate electromagnetically induced transparency (EIT) in a sample of rubidium atoms, trapped in an optical dipole trap. Mixing a small amount of $σ^-$-polarized light to the weak $σ^+$-polarized probe pulses, we are able to measure the absorptive and dispersive properties of the atomic medium at the same time. Features as small as 4 kHz have been detected on an absorption line with 20 MHz line width.

quant-ph↗