Bang-bang shortcut to adiabaticity in the Dicke model as realized in a Penning trap experiment

Fast and stable manipulation of a charged particle in a Penning trap

We propose shortcuts to adiabaticity which achieve fast and stable control of the state of a charged particle in an electromagnetic field. In particular we design a non-adiabatic change of the magnetic field strength in a Penning trap which changes the radial spread without final excitations. We apply a streamlined version of the fast-forward formalism as well as an invariant based inverse engineering approach. We compare both methods and examine their stability.

Population dynamics in sideband cooling of trapped ions outside the Lamb-Dicke regime

We present the results of simulations of optical sideband cooling of atomic ions in a trap with a shallow potential well. In such traps, an ion cannot be Doppler cooled near to the Lamb-Dicke regime ($η^2(2n+1) \ll 1$). Outside the Lamb-Dicke regime, the sideband cooling dynamics are altered by the existence of various Fock states where the cooling becomes very slow. A calcium ion trapped in our Penning trap realises such a situation, hence single stage cooling is inefficient to prepare the ion in the motional ground state. For these systems, it is necessary to study the cooling dynamics in de…

Sideband cooling of small ion Coulomb crystals in a Penning trap

We have recently demonstrated the laser cooling of a single $^{40}$Ca$^+$ ion to the motional ground state in a Penning trap using the resolved-sideband cooling technique on the electric quadrupole transition S$_{1/2} \leftrightarrow$ D$_{5/2}$. Here we report on the extension of this technique to small ion Coulomb crystals made of two or three $^{40}$Ca$^+$ ions. Efficient cooling of the axial motion is achieved outside the Lamb-Dicke regime on a two-ion string along the magnetic field axis as well as on two- and three-ion planar crystals. Complex sideband cooling sequences are required in or…

使用空间光调制器对彭宁阱中的大离子晶体进行局部控制

Localized control of large ion crystals in a Penning trap using a spatial light modulator

研究利用空间光调制器对彭宁阱中大离子晶体进行局部控制，通过施加可编程交流斯塔克位移图案实现，验证了该技术并为彭宁阱中单个离子寻址提供途径。

高效三维度子德普勒冷却 $^{40}$Ca$^+$ 在Penning陷阱中

Efficient Three-Dimensional Sub-Doppler Cooling of $^{40}$Ca$^+$ in a Penning Trap

通过参数驱动和双光子暗共振实现 $^{40}$Ca$^+$ 离子在Penning陷阱中的三维子德普勒冷却，显著降低轴向模式占据数。