Vapor cells for atomic physics sensors.

Abstract

One embodiment includes a vapor cell for an atomic physics based sensor system. The vapor cell includes a cell wall formed from a substantially transparent material. The cell wall can encapsulate an alkali metal vapor and can include an inner surface and an outer surface. The vapor cell also includes at least one structural feature disposed on at least one of the inner surface and the outer surface of the cell wall and extending along a portion of a corresponding one of the inner surface and the outer surface.

Description

[Technical field]

[0001] The present invention relates generally to sensor systems, and more particularly to vapor cells for atomic physics sensors. [Background technology]

[0002] Various precision sensor systems incorporate atomic physics to measure any of a variety of parameters, such as time, inertial parameters, magnetic fields, and electric fields. Such precision sensor systems typically include optical and / or radio frequency (RF) signals that interact with atoms (e.g., alkali metal atoms) provided in a vapor matter state within a vapor cell. Examples of such sensor systems include nuclear magnetic resonance (NMR) sensors, electron paramagnetic resonance (EPR) sensors, interferometric sensors, and / or electrometer sensors. The sensor systems typically include one or more optical beams that are provided to pass through the vapor cell such that a characteristic of a detection beam exiting the vapor cell is monitored. The interaction of the optical beam and any external stimuli (e.g., magnetic field, RF signal, etc.) with the atoms contained in the vapor cell can provide a measurable parameter of the detection beam that is monitored to enable measurement of a measurable parameter (e.g., rotation, acceleration, magnetic field, electric field, and / or time). Summary of the Invention

[0003] One embodiment includes a vapor cell for an atomic physics based sensor system. The vapor cell includes a cell wall formed from a substantially transparent material. The cell wall can encapsulate an alkali metal vapor and can include an inner surface and an outer surface. The vapor cell also includes at least one structural feature disposed on at least one of the inner surface and the outer surface of the cell wall and extending along a portion of a corresponding one of the inner surface and the outer surface.

[0004] Another example includes a method of forming a vapor cell for an atomic physics based sensor system. The method includes forming a cell wall from a substantially transparent material. The cell wall includes an inner surface and an outer surface. The method also includes forming at least one structural feature on at least one of the inner surface and the outer surface of the cell wall, the structural feature extending along a corresponding portion of at least one of the inner surface and the outer surface. The method further includes sealing the vapor cell to enclose an alkali metal vapor within the vapor cell.

[0005] Another example includes an atomic physics-based sensor system. The system includes a vapor cell. The vapor cell includes a cell wall formed from a substantially transparent material. The cell wall can encapsulate an alkali metal vapor and can include an inner surface and an outer surface. The vapor cell can also include at least one structural feature disposed on at least one of the inner surface and the outer surface of the cell wall and extending along a portion of a corresponding one of the inner surface and the outer surface. The system also includes at least one laser configured to provide a respective at least one light beam through the vapor cell and at least one radio frequency (RF) signal generator configured to provide an RF signal through the vapor cell. The system further includes a detection system configured to monitor a detection beam corresponding to one of the at least one light beam exiting the vapor cell to determine a measurable parameter. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 illustrates an exemplary block diagram of a vapor cell. [Diagram 2] FIG. 1 shows an exemplary schematic diagram of a vapor cell. [Diagram 3] FIG. 1 illustrates an example of a sensor based on atomic physics. [Figure 4] FIG. 1 illustrates an example of a method for fabricating a vapor cell for an atomic physics based sensor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] The present invention relates generally to sensor systems, and more particularly to vapor cells for atomic physics sensors. For example, the vapor cell may be implemented in a nuclear magnetic resonance (NMR) sensor, an electron paramagnetic resonance (EPR) sensor, an interferometer sensor, and / or an electrometer sensor. The vapor cell has a cell wall formed of a substantially transparent material (e.g., a type of glass material, a transparent ceramic, a crystal such as quartz). The cell wall may contain an alkali metal vapor (e.g., rubidium (Rb) or cesium (Cs)) within, for example, an otherwise evacuated volume, and may include an inner surface and an outer surface. The vapor cell may also include at least one structural feature provided on at least one of the inner surface and the outer surface of the cell wall.

[0008] The structural feature(s) can extend along a portion of at least one of the corresponding inner and outer surfaces of the vapor cell and can be formed in a variety of different ways (e.g., rings, ribs, bars, arches, fins, combinations thereof, etc.). As an example, the structural feature(s) can provide structural integrity for the vapor cell, allowing the cell walls of the vapor cell to be fabricated very thin to provide higher transmission of signals (e.g., RF signals) through the cell walls and thus provide approximate transparency to the signals, while still maintaining sufficient structural integrity to mitigate breakdown based on pressure gradients between the inner and outer surfaces. As another example, the structural feature(s) can be selected to modify signal propagation to improve sensor performance. For example, the structural feature(s) can create regions of altered dielectric constant that can modify the characteristics of the electric, RF, and optical fields within the vapor cell. In yet another example, the structural feature(s) can give rise to regions of varying magnetic permeability, which can modify the magnetic field characteristics within the cell.

[0009] The structural feature(s) can be provided or formed in any of a variety of ways based on design goals. As a first example, the structural feature(s) can be implemented integrally with the cell wall of the vapor cell. For example, to form the structural feature(s), a portion of the cell wall can be etched to a first thickness between the inner and outer surfaces. Thus, the area of ​​the cell wall between the etched portions can correspond to the structural feature(s) having a thickness greater than the first thickness. As a second example, the structural feature(s) can be a separate component bonded to at least one of the inner and outer surfaces of the cell wall. As an example, such a separate component can have a higher tensile strength and / or be formed from a thicker material than the substantially transparent material from which the cell wall is formed. In either example, the cell wall can have a smaller surface area devoted to the total surface area of ​​the portion on which the structural feature(s) is provided or formed than the total surface area of ​​the portion without the structural feature(s). Thus, thinner sections of the cell wall may be more effective at promoting approximate transmission of a signal (eg, an RF signal) through the cell wall and into the volume of the vapor cell that confines the alkali metal vapor.

[0010] 1 shows an example block diagram of vapor cell 100. Vapor cell 100 may be implemented in any of a variety of atomic physics-based sensors, such as a nuclear magnetic resonance (NMR) sensor, an electron paramagnetic resonance (EPR) sensor, an interferometer sensor, and / or an electrometer sensor. Vapor cell 100 may be configured to contain an alkali metal vapor, such as rubidium (Rb) or cesium (Cs), for example, in an otherwise evacuated volume.

[0011] In the example of FIG. 1, vapor cell 100 includes cell wall 102 formed from a substantially transparent material (e.g., a type of glass material such as quartz). As described herein, the substantially transparent material may be sufficient to provide a high transmission of a signal (e.g., an optical signal or a radio frequency (RF) signal) through cell wall 102, e.g., about 95% or more. Thus, the optical beam and the RF signal may interact with the alkali metal vapor within vapor cell 100. As an example, a detection beam corresponding to the optical beam (e.g., a probe beam) exiting vapor cell 100 may be monitored (e.g., by a detection system) to determine a characteristic of the detection beam. The characteristic of the detection beam may be altered by the interaction of the signal with the alkali metal atoms to allow for the measurement of a measurable parameter (e.g., time, rotation, acceleration, magnetic field, and / or electric field).

[0012] Cell wall 102 includes an inner surface that encloses the volume of vapor cell 100 and an outer surface that is exposed to the exterior of vapor cell 100. In the example of Figure 1, vapor cell 100 includes at least one structural feature 104 disposed on at least one of the inner and outer surfaces of cell wall 102. Structural feature(s) 104 may extend along a portion of at least one of the inner and outer surfaces of vapor cell 100. For example, each of structural feature(s) 104 may extend along a length of cell wall 102, may extend around (e.g., circumnavigate) cell wall 102, or may be provided in any of a variety of ways.

[0013] As an example, the structural feature(s) 104 may be configured to enhance the structural integrity of the cell wall 102. Thus, the portion of the cell wall 102 without the structural feature(s) 104 may be fabricated to be very thin to provide a higher transmission of signals (e.g., RF signals) passing through the cell wall 102, thus providing a similar transparency to the signals. However, the presence of the structural feature(s) 104 may maintain sufficient structural integrity to mitigate collapse based on pressure gradients between the inner and outer surfaces of the cell wall 102. The structural feature(s) 104 may be provided or formed in any of a variety of ways that provide sufficient structural integrity while maintaining a similar transparency to incident signals (e.g., both optical and RF signals) passing through the cell wall 102 and entering the vapor cell 100.

[0014] As a first example, the structural feature(s) 104 may be formed from the same substantially transparent material that forms the cell wall 102. As a further example, the structural feature(s) 104 may be integral with the cell wall 102 of the vapor cell 100. For example, to form the structural feature(s) 104, a portion of the cell wall 102 may be chemically etched to a first thickness between the inner and outer surfaces. Thus, the area of ​​the cell wall 102 between the etched portions may correspond to the structural feature(s) having a thickness greater than the first thickness. As a second example, the structural feature(s) 104 may be a separate component bonded to at least one of the inner and outer surfaces of the cell wall 102. As an example, such a separate component may have a higher tensile strength and / or may be formed from a thicker material than the substantially transparent material from which the cell wall 102 is formed.

[0015] The cell walls 102 may have a smaller surface area devoted to the total surface area where the structural feature(s) 104 are provided or formed than the total surface area where the structural feature(s) 104 are not present. Thus, the total surface area of ​​the cell walls 102, which includes a thinner and more substantially transparent material, may be more effective at allowing a greater transmission of a signal provided through the cell walls 102 to interact with the alkali metal vapor trapped within the vapor cell 100. Thus, the cell walls 102 may facilitate a transmission that approximates a signal (e.g., an RF signal) passing through the cell walls 102 and entering the volume of the vapor cell 100 that confines the alkali metal vapor (e.g., while maintaining sufficient structural integrity to mitigate against the breakdown of the cell walls 102 based on a pressure gradient between the inner and outer surfaces of the cell walls 102). For example, assuming the volume enclosed by the cell walls 102 is evacuated with nothing but the alkali metal vapor, the cell walls 102 may be imploded by external pressure. Alternatively, in a sensor system used in outer space, lack of atmospheric pressure may cause cell wall 102 to burst. In any event, vibration and / or inertial shock may cause the destruction of cell wall 102. However, by implementing structural feature(s) 104, vapor cell 100 may exhibit sufficient structural integrity to withstand environmental stresses while still providing excellent transmission rates based on very thin cell wall 102.

[0016] As another example, the structural feature(s) 104 may be alternatively or additionally implemented for a variety of other reasons other than the structural integrity of the cell wall 102. As an example, the structural feature(s) 104 may be implemented to affect the signals and / or fields incident on the volume within the vapor cell 100 in a variety of different ways. As an example, by implementing the structural feature(s) 104 as a spatially varying wall thickness of the cell wall 102, the dielectric constant of the material of the cell wall 102 may be spatially varied as well. Thus, the propagation direction, diffraction, and / or reflection characteristics of the RF signal may be affected by the structural feature(s) 104. As another example, by implementing the structural feature(s) 104 as a spatially varying wall thickness of the cell wall 102, the magnetic permeability of the cell wall 102 may be affected in a similar manner to the dielectric constant discussed above. Thus, the magnetic field passing through the cell wall 102 may be manipulated. As an example, the magnetic permeability may be affected to provide approximate uniformity of the magnetic field within the volume of the cell wall 102, or to block spurious magnetic fields entering the volume within the cell wall 102 to reduce noise effects on an associated sensor or system. Thus, the structural feature(s) 104 may be provided for a variety of purposes.

[0017] FIG. 2 shows an exemplary diagram of a vapor cell 200. The vapor cell 200 may be implemented in any of a variety of atomic physics-based sensors, such as an NMR sensor, an EPR sensor, an interferometer sensor, and / or an electrometer sensor. The vapor cell 200 may be configured to encapsulate an alkali metal vapor, such as Rb or Cs, for example, in an otherwise vacuum volume. The example of FIG. 2 shows an exploded view 202 for illustrating a portion (e.g., one end) of the vapor cell 200 in a larger scale. The vapor cell 200 may correspond to the vapor cell 100 in the example of FIG. 2. Thus, the following description of the example of FIG. 2 refers to the example of FIG. 1.

[0018] In the example of FIG. 2, vapor cell 200 is shown as being cylindrical and thus having a tubular shape. Although the particular example of FIG. 2 is shown as being cylindrical, other tubular configurations (e.g., a prism with a rectangular, square, or triangular cross section) are possible. Vapor cell 200 includes a cell wall 204 formed from a substantially transparent material (e.g., a type of glass material such as quartz). Thus, the light beam and the RF signal can interact with the alkali metal vapor within vapor cell 100. As described above in the example of FIG. 2, cell wall 204 includes an inner surface that encloses the volume of vapor cell 200 and an outer surface that is exposed to the exterior of vapor cell 200.

[0019] In the example of FIG. 2, the vapor cell 200 also includes a number of structural features 206 disposed on the outer surface of the cell wall 204. The structural features 206 are shown as an arrangement of a number of rings disposed periodically along the length of the tubular shape of the vapor cell 100. The rings that make up the structural features 206 are parallel to one another and extend around the cross section of the vapor cell 100 such that the rings circumnavigate the cell wall 102. Thus, the portion of the cell wall 204 where the structural features 206 are absent can be fabricated to be very thin to provide a higher transmission of a signal (e.g., an RF signal) passing through the cell wall 204, and thus provide a similar transmission to the signal. However, as an example, the presence of the structural features 206 can maintain sufficient structural integrity of the cell wall 204. As another example, the structural features 206 can affect the properties of the cell wall 204, such as with respect to the dielectric permeability and / or magnetic permeability of the cell wall 204. Thus, the structural features 206 may additionally or alternatively be implemented to affect RF signals and / or magnetic fields passing through the cell walls 204 .

[0020] As discussed above, the structural features 206 may be provided or formed in any of a variety of ways to provide sufficient structural integrity while maintaining near transparency to incident signals (e.g., both optical and RF) passing through the cell walls 204 and entering the vapor cell 200. As a first example, the structural features 206 may be integrated with the cell walls 204 of the vapor cell 200. For example, to form the structural features 206, the material forming the vapor cell 100 may be etched around the outer edge of its cross section in periodic portions. Thus, the unetched portions of the material may simply not be etched and thus remain thicker relative to the cross section of the vapor cell 200 to form the structural features 206. The etched portions may thus correspond to the cell walls 204 between each of the structural features 206. Thus, the etched portions corresponding to the cell walls 204 may be much thinner relative to the cross section of the vapor cell 200 than the structural features 206.

[0021] The portions of cell wall 204 where structural feature 206 is not present may comprise a much larger overall portion of the total surface area of ​​cell wall 204 than the portions of cell wall 204 where structural feature 206 is present. Stated another way, when structural feature 206 and cell wall 204 are integral with one another, cell wall 204 may comprise a much larger overall portion of the total surface area of ​​the exterior of vapor cell 200 than structural feature 206. Thus, as an example, based on a combination of the much thinner material of cell wall 204 and the greater surface area of ​​cell wall 204 relative to structural feature 206, vapor cell 200 may exhibit greater permeability of signals provided through cell wall 204 to interact with alkali metal vapor trapped within vapor cell 200. Thus, the cell wall 204 can promote permeability approximating that of a signal (e.g., an RF signal) passing through the cell wall 204 and entering the volume of the vapor cell 200 that confines the alkali metal vapor, while maintaining sufficient structural integrity to mitigate breakage of the cell wall 204 based on, for example, a pressure gradient between the inner and outer surfaces of the cell wall 204.

[0022] Vapor cell 200 is provided as an example, and other configurations are possible. For example, structural features 206 may be implemented in any of a variety of ways other than the ring structure shown in the example of FIG. 2. Examples include one or more elongated portions extending along the tubular length of vapor cell 200, spiral or crisscross patterns along the tubular length of vapor cell 200, chevrons, patches, or other types of arrangements of structural features 206. Thus, vapor cell 200 may be implemented in any of a variety of ways.

[0023] 3 illustrates an example of an atomic physics based sensor system 300. The sensor system 300 may correspond to an NMR sensor, an EPR sensor, an interferometer sensor, or an electrometer sensor. Thus, the sensor system 300 may be implemented to measure any of a variety of measurable parameters, such as time, rotation, acceleration, magnetic field, and / or electric field.

[0024] The sensor system 300 includes a vapor cell 302, which may be configured as a sealed glass vessel containing a vapor of alkali metal atoms. The vapor cell 302 may correspond, for example, to the vapor cells 100 and / or 200 described above in the respective examples of FIGS. 1 and 2. The sensor system 300 also includes an optical signal system 304 configured to generate at least one optical beam, shown as a signal OPT in the example of FIG. 3. As an example, the optical signal system 304 may include a probe laser and at least one combined laser for generating a probe beam and at least one combined beam, respectively. As another example, the optical signal system 304 may include a pump laser and a probe laser for generating separate corresponding pump beams and probe beams. Each of the optical beams OPT may be provided to pass through the vapor cell 302 via an optical system (not shown), for example, to provide an interaction with the alkali metal vapor in the vapor cell 302 (e.g., to provide optical pumping and / or energy state transitions). In the example of FIG. 3, one of the optical beams OPT is a detection beam OPT. DETmay exit the vapor cell 302 as

[0025] The sensor system 300 also includes a signal system 306 configured to generate any of a variety of signals or fields, shown in the example of FIG. 3 as signals SIG. As an example, the signal system 306 may include a split signal generator configured to generate the signal SIG as a split signal provided through the vapor cell 302 at a predetermined frequency and a predetermined amplitude to split a frequency spectrum transmission peak corresponding to a first Rydberg energy state of the alkali metal atom into a pair of Autler-Townes frequency spectrum transmission peaks associated with the alkali metal atom. As another example, the signal system 306 may include a tuning signal generator capable of generating a tuning RF signal to tune the energy difference between the Rydberg energy states of the alkali metal atom. The signal system 306 may additionally or alternatively include a magnetic field generator configured to generate one or more magnetic fields provided through the vapor cell 302, such as to cause precession of the alkali metal vapor contained in the vapor cell 302. As described herein, the arrangement of the cell walls and structural feature(s) of vapor cell 302 is such that the cell walls of vapor cell 302 can be substantially transparent to the signal RF, e.g., can provide greater interaction between the alkali metal vapor and the signal SIG while maintaining sufficient structural integrity to mitigate damage to vapor cell 302. As another example, the structural feature(s) of vapor cell 302 can be such that the signal SIG (e.g., RF signal(s) and / or magnetic field(s)) can be manipulated as the signal SIG passes through the cell walls of vapor cell 302.

[0026] The sensor system 300 includes a detection beam OPT DETFor example, the detection system 308 may include a detection beam OPT based on the interaction of the alkali metal atoms with the light beam(s) OPT and a signal RF and an external stimulus (e.g., acceleration, rotation, external RF signal, external magnetic field, etc.). DET The characteristics of the detection beam can be monitored. DET The characteristic may be intensity, phase, Faraday rotation, or any of a variety of other light beam characteristics. The detection system 308 may include a photodetector capable of monitoring the characteristic. Accordingly, an associated processor (not shown) may be implemented to measure a measurable parameter based on the monitored characteristic.

[0027] Thus, based on the cell wall and structural feature(s) of vapor cell 302 as described herein, sensor system 300 may be implemented in any of a variety of harsh environments to provide accurate determination of measurable parameters while maintaining sufficient structural integrity of the cell wall of vapor cell 302.

[0028] In view of the above structural and functional features described above, methods according to various embodiments of the present disclosure may be better understood with reference to Figure 4. It should be understood and appreciated that some aspects, according to the present disclosure, may occur in a different order and / or simultaneously with other aspects than as shown and described herein, and therefore the method of Figure 4 is not limited by the order shown. Furthermore, not all illustrated features are required to practice a method according to an embodiment of the present invention.

[0029] 4 illustrates an example of a method 400 for forming a vapor cell (e.g., vapor cell 100) for an atomic physics-based sensor system (e.g., sensor system 300). At 402, a cell wall (e.g., cell wall 102) is formed from a substantially transparent material. The cell wall may include an inner surface and an outer surface. At 404, at least one structural feature (e.g., structural feature(s) 104) is formed on at least one of the inner and outer surfaces of the cell wall and extending along a corresponding portion of at least one of the inner and outer surfaces. At 406, the vapor cell is sealed to confine an alkali metal vapor (e.g., Rb or Cs) within the vapor cell.

[0030] The above are examples of the present invention. Of course, it is not possible to describe every conceivable combination of elements or methods for purposes of describing the present invention, but one skilled in the art will recognize that many more combinations and permutations of the present invention are possible. Accordingly, the present invention is intended to embrace all such changes, modifications, and variations that fall within the spirit and scope of the appended claims. In addition, when the disclosure or claims recite "a," "an," "a first," or "another" element, or the equivalent thereof, it should be construed as including one or more such elements, and does not require or exclude two or more such elements. As used herein, the term "includes" means including but not limited to, and the term "including" means including but not limited to. The term "based on" means based at least in part on. The technical ideas that can be understood from the above-described embodiment will be described below as supplementary notes. [Appendix 1] 1. A vapor cell for an atomic physics based sensor system, comprising: a cell wall formed from a substantially transparent material, the cell wall containing an alkali metal vapor and having an inner surface and an outer surface; at least one structural feature disposed on at least one of the inner and outer surfaces of the cell wall and extending along a corresponding portion of the at least one of the inner and outer surfaces. [Appendix 2] 2. The cell of claim 1, wherein a corresponding one of the inner and outer surfaces of the cell wall having the at least one structural feature has a total surface area that includes a total surface area of ​​a first portion having the at least one structural feature and a total surface area of ​​a second portion not having the at least one structural feature, the total surface area of ​​the second portion being greater than the total surface area of ​​the first portion. [Appendix 3] 2. The cell of claim 1, wherein the at least one structural feature is formed from the substantially transparent material. [Appendix 4] 2. The cell of claim 1, wherein the at least one structural feature is integrally formed with the cell wall. [Appendix 5] 5. The cell of claim 4, wherein the cell wall has a first thickness between the inner surface and the outer surface, and each of the at least one structural feature is disposed as a portion of the cell wall having a thickness greater than the first thickness. [Appendix 6] 5. The cell of claim 4, wherein the at least one structural feature is formed by chemically etching portions of the exterior surface of the cell walls to form the at least one structural feature between etched portions of the exterior surface of the cell walls. [Appendix 7] 2. The cell of claim 1, wherein the cell wall is configured as a tubular vapor cell, and the at least one structural feature is formed as a plurality of rings circumnavigating a corresponding one of the outer surface and the inner surface of the cell wall and arranged parallel to one another along a length of the tubular vapor cell. [Appendix 8] 2. The cell of claim 1, wherein the at least one structural feature is disposed as at least one individual discrete component joined to the at least one of the exterior surface and the interior surface. [Appendix 9] 2. A physics-based sensor system comprising the vapor cell of claim 1. [Appendix 10] 1. A method of forming a vapor cell for an atomic physics based sensor system, comprising: forming a cell wall from a substantially transparent material, the cell wall having an inner surface and an outer surface; forming at least one structural feature on at least one of the interior and exterior surfaces of the cell walls such that the structural feature extends along a portion of a corresponding at least one of the interior and exterior surfaces; and sealing the vapor cell to contain an alkali metal vapor within the vapor cell. [Appendix 11] 11. The method of claim 10, wherein a corresponding one of the interior and exterior surfaces of the cell wall on which the at least one structural feature is formed has a total surface area that includes a total surface area of ​​a first portion on which the at least one structural feature is formed and a total surface area of ​​a second portion on which the at least one structural feature is not present, the total surface area of ​​the second portion being greater than the total surface area of ​​the first portion. [Appendix 12] 11. The method of claim 10, wherein forming the at least one structural feature includes forming the at least one structural feature integral with the cell wall. [Appendix 13] 13. The method of claim 12, wherein forming the at least one structural feature integral with the cell walls comprises chemically etching a portion of the exterior surface of the cell walls to form the at least one structural feature between etched portions of the exterior surface of the cell walls. [Appendix 14] 11. The method of claim 10, wherein forming the cell walls includes forming the cell walls to have a first thickness between the inner surface and the outer surface, and forming the at least one structural feature includes forming the at least one structural feature as a portion of the cell wall having a thickness greater than the first thickness. [Appendix 15] 11. The method of claim 10, wherein forming the cell wall includes forming the cell wall as a tubular vapor cell, and forming the at least one structural feature includes forming the at least one structural feature as a plurality of rings circumnavigating corresponding ones of the exterior and interior surfaces of the cell wall and arranged parallel to one another along a length of the tubular vapor cell. [Appendix 16] 1. A physics-based sensor system, comprising: 1. A vapor cell comprising: a cell wall formed from a substantially transparent material, the cell wall containing an alkali metal vapor and having an inner surface and an outer surface; the vapor cell including at least one structural feature disposed on at least one of the inner and outer surfaces of the cell wall and extending along a corresponding portion of the at least one of the inner and outer surfaces; at least one laser configured to provide at least one respective light beam through said vapor cell; at least one radio frequency (RF) signal generator configured to provide an RF signal through the vapor cell; a detection system configured to monitor a detection beam corresponding to one of the at least one light beams exiting the vapor cell to determine a measurable parameter. [Appendix 17] 17. The system of claim 16, wherein the corresponding one of the interior and exterior surfaces of the cell wall on which the at least one structural feature is provided has a total surface area that includes a total surface area of ​​a first portion on which the at least one structural feature is provided and a total surface area of ​​a second portion on which the at least one structural feature is absent, the total surface area of ​​the second portion being greater than the total surface area of ​​the first portion. [Appendix 18] 17. The system of claim 16, wherein the at least one structural feature is integrally formed with the cell wall. [Appendix 19] 19. The system of claim 18, wherein the cell wall has a first thickness between the inner surface and the outer surface, and each of the at least one structural feature is disposed as a portion of the cell wall having a thickness greater than the first thickness. [Appendix 20] 19. The system of claim 18, wherein the at least one structural feature is formed by chemically etching portions of the exterior surface of the cell walls to form the at least one structural feature between etched portions of the exterior surface of the cell walls.

Claims

1. 1. A vapor cell for an atomic physics based sensor system, comprising: a cell wall formed from a substantially transparent material, the cell wall containing an alkali metal vapor and having an inner surface and an outer surface, the cell wall having a first thickness between the inner surface and the outer surface; at least one structural feature disposed on at least one of the interior and exterior surfaces of the cell wall and extending along a portion of a corresponding one of the at least one of the interior and exterior surfaces, each of the at least one structural feature having a second thickness greater than the first thickness, and the cell wall having a dielectric constant that varies between the first thickness and the second thickness.

2. 2. The cell of claim 1, wherein a corresponding one of the interior and exterior surfaces of the cell wall having the at least one structural feature thereon has a total surface area that includes a total surface area of ​​a first portion having the at least one structural feature thereon and a total surface area of ​​a second portion not having the at least one structural feature thereon, the total surface area of ​​the second portion being greater than the total surface area of ​​the first portion.

3. The cell of claim 1 , wherein the at least one structural feature is formed from the substantially transparent material.

4. The cell of claim 1 , wherein the at least one structural feature is integrally formed with the cell wall.

5. 5. The cell of claim 4, wherein the at least one structural feature is formed by chemically etching portions of the exterior surface of the cell walls to form the at least one structural feature between etched portions of the exterior surface of the cell walls.

6. 2. The cell of claim 1 , wherein the cell wall is configured as a tubular vapor cell and the at least one structural feature is formed as a plurality of rings circumnavigating a corresponding one of the exterior and interior surfaces of the cell wall and arranged parallel to one another along a length of the tubular vapor cell.

7. The cell of claim 1 , wherein the at least one structural feature is disposed as at least one individual separate component bonded to the at least one of the exterior surface and the interior surface.

8. A physics-based sensor system comprising the vapor cell of claim 1 .

9. 1. A method of forming a vapor cell for an atomic physics based sensor system, comprising: forming a cell wall from a substantially transparent material having a first thickness between an inner surface and an outer surface; forming at least one structural feature on at least one of the interior and exterior surfaces of the cell walls, the structural feature having a second thickness greater than the first thickness and extending along a portion of a corresponding at least one of the interior and exterior surfaces, the cell walls having a dielectric constant that varies between the first thickness and the second thickness; and sealing the vapor cell to contain an alkali metal vapor within the vapor cell.

10. 10. The method of claim 9, wherein a corresponding one of the interior and exterior surfaces of the cell wall on which the at least one structural feature is formed has a total surface area that includes a total surface area of ​​a first portion on which the at least one structural feature is formed and a total surface area of ​​a second portion on which the at least one structural feature is not present, the total surface area of ​​the second portion being greater than the total surface area of ​​the first portion.

11. The method of claim 9 , wherein forming the at least one structural feature comprises forming the at least one structural feature integral with the cell wall.

12. 12. The method of claim 11 , wherein forming the at least one structural feature integral with the cell walls comprises chemically etching a portion of the exterior surface of the cell walls to form the at least one structural feature between etched portions of the exterior surface of the cell walls.

13. 10. The method of claim 9, wherein forming the cell wall comprises forming the cell wall as a tubular vapor cell, and forming the at least one structural feature comprises forming the at least one structural feature as a plurality of rings circumnavigating a corresponding one of the exterior and interior surfaces of the cell wall and positioned parallel to one another along a length of the tubular vapor cell.

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