# Long-Time Bit Storage and Retrieval without Cold Atom Technology

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## Abstract

**:**

## 1. Introduction

## 2. Theoretical Model (Methods)

#### 2.1. Notation

#### 2.2. Skeleton Formulas

#### 2.3. Limits on n

#### 2.4. Pump

## 3. Physics (Preliminary Results)

## 4. Delayed Bit Retrieval (Final Results and Discussion)

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**${\alpha}_{1}=1,{\alpha}_{2}={\alpha}_{0}=0$. Creation (

**a**) and later decay (

**b**) at rate ${\Gamma}_{1}$ of single Nyxion with no continuous (dc) pump; early subradiant emission (

**c**) from “dark” state.

**Figure 2.**${\alpha}_{1}={\alpha}_{2}=1,{\alpha}_{0}=0$ and $5\beta =400$. A bit “stored” at $T=5$ (creation not shown here, similar to Figure 1a) is “read” by a second pulse at $T=400$ (

**a**,

**b**), and a superradiant flash (

**c**) is produced.

**Figure 3.**${\alpha}_{1}=0,{\alpha}_{2}={\alpha}_{0}=1,\phantom{\rule{0.277778em}{0ex}}5\beta $ = 100,000 and $\delta =0.001687$. The dc pump is turned on at $T=5$, without an accompanying pulse, but with the relative continuous (dc) pump strength slightly greater than ${\delta}_{crit}$. Excitation grows (

**a**) with time constant ${\Gamma}_{1}$ toward steady-state value $n=-0.2$. At T =100,000 = 100${\Gamma}_{1}^{-1}$, a “reading pulse” is applied. An “Aurora” results, shown as a temporary superexcitation of n (

**b**) and an immediately following superradiant emission (

**c**) in the forward direction.

**Figure 4.**(

**a**–

**c**) ${\alpha}_{1}=0,{\alpha}_{2}={\alpha}_{0}=1,\phantom{\rule{0.277778em}{0ex}}5\beta $ = 100,000 and $\delta =0.001686$. Same parameters as in Figure 3 except that $\delta $ has been set slightly lower than ${\delta}_{crit}$. The Aurora following the “reading pulse” does not take place (

**b**,

**c**).

**Figure 5.**${\alpha}_{1}={\alpha}_{2}={\alpha}_{0}=1,\phantom{\rule{0.277778em}{0ex}}5\beta $ = 100,000 and $\delta =0.0016860$. Both continuous (dc) pump and “storage” pulse are turned on together at $T=5$. The initial reaction (

**a**) is dominated by the initial pulse. (Slight overshoot of $n=-0.2$ is corrected at $T=70$.) After reaching $n=-0.2$, the system does not decay as shown in Figure 1a,b, but is maintained by the dc pump at $n=-0.2$ until it is discharged (

**b**,

**c**) by the “reading” pulse. The relative dc pump strength has been set below${\delta}_{crit}$ so that the discharge would not have taken place in the absence of the initial storage pulse (compare with Figure 4b,c).

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**MDPI and ACS Style**

Friedberg, R.; Manassah, J.T.
Long-Time Bit Storage and Retrieval without Cold Atom Technology. *Symmetry* **2022**, *14*, 1505.
https://doi.org/10.3390/sym14081505

**AMA Style**

Friedberg R, Manassah JT.
Long-Time Bit Storage and Retrieval without Cold Atom Technology. *Symmetry*. 2022; 14(8):1505.
https://doi.org/10.3390/sym14081505

**Chicago/Turabian Style**

Friedberg, Richard, and Jamal T. Manassah.
2022. "Long-Time Bit Storage and Retrieval without Cold Atom Technology" *Symmetry* 14, no. 8: 1505.
https://doi.org/10.3390/sym14081505