Tweezer Clock

It isn’t easy to control the atoms. They can even tunnel out of the containment or can zip around. For quantum devices to work well and new measurement tools, scientists need to manipulate and control atoms as much as possible. The optimal tweezer clocks provide a new twist and possibilities in timekeeping based on an array of individually trapped atoms. It has the capacity for low noise as one can measure the frequency of the clock at once. While the entangled atomic clocks tell time, the new tweezer clock offers great possibilities to measure time precisely. 

An overview of the Tweezer Clock 

The researchers at NASA designed the new tweezer clock- Jet Propulsion Laboratory (JPL) and California Institute of Technology, providing more precise and accurate time, in contrast with the entangled atomic clocks which are used at present. The standard atomic clocks used at present tell time on the count of radio frequencies based on the atom caesium. The tweezer clock is built upon the two optical entangled atomic clock types already in use. The first type uses the single trapped charged atom, whereas the second one is based on thousand neutral atoms. The clock’s design utilizes 40 atoms, which can be manipulated and controlled with the help of a laser tweezer. 

As clocks are always in demand, it is why precision timekeeping is purchased for various application purposes starting from communication and navigation to searches beyond standard model physics and radio astronomy. The most precise clocks with trapped atoms utilize the optical frequency under clock transition between two atomic states. The cycle of the frequency offers the clock’s precise tick. Among the advanced optical entangled atomic clocks, there are two types on which the researchers have focused mainly. The first type explores the electrons of a single trapped atom, and the second one explores the electrons in various atoms. Today the two groups have brought the third type of optical clock with trapped atoms into the timekeeping landscape, i.e., the tweezer clock. 

It comprises distinct optical traps, called optical tweezers, containing one atom. Basing a clock on a single ion helps manipulate and isolate particles from the outside world. This, in turn, sets a limit for the effect of twisting the electron’s ticking rate. Although, the atomic state’s uncertainty bounds the precision of tweezer clocks. 

Following the optical lattice clocks, the noise of the quantum projection can be averaged by exploring a thousand frequency atoms at once. In contrast with the single atom case, the noise descends as per the square root of the atom’s numbers, resulting in good precision in a provided measurement period. 

The tweezer clock compromises a lattice approach and a single ion. Although it is a tightly focused laser beam, it helps pull the small objects or atoms to the narrowest point. Meanwhile, the number of atoms present is sufficient to decrease the quantum noise in the single-atom case. These atoms suppress disruptive atomic interaction as they are well spaced by various micrometres. For each tweezer, the clock offers a single-particle readout. 

Steps to set up new Clocks

Setting up the new clock involves a few steps. Following are the steps required to set up new clocks- 

Step1: Laser cooling the strontium gas. A strontium gas is an atomic species for which the electronic structure suits any optical look

Step2: Loading the atoms into the optical tweezer’s array, which forms by passing a laser with the help of an objective lens and an acousto-optic deflector. However, the loading of the atoms doesn’t ensure a single atom per tweezer, as some tweezers have multiple atoms and some have zero atoms. The scientist utilizes an additional tweezer to eliminate atoms from excess atoms resulting in unfilled empty tweezers

Step3: Last, the researchers cross-question every tweezer atom. The process demands modulating the frequency of the laser till the atom’s fluorescence can be read out in the camera

Following the single-particle readout of the setup, scientists can measure the clock transition after effects occurring from the tweezer’s optical field. The future goal of the optical tweezer clock is to enhance the clock’s performance by combining the single-particle interrogation and control with a single-particle readout. Such changes can result in a more convenient platform for the optical tweezer clock for zero dead-time configurations. Hence, these can emerge as a more efficient platform for quantum measurements than the entangled atomic clocks.

Conclusion 

To reach the lower quantum noise levels, it is necessary to scale the tweezer clock to large atom numbers. The tweezers clock offers an emerging platform for quantum measurements and quantum computation. Improvements in any of the fields will surely offer advances in clock precision. Stating all the possibilities, it is confirmed that the future improvements in the tweezer clock can bring positive results in quantum control and timekeeping which the entangled atomic clocks are less likely to offer.