Umeå University's logo

umu.sePublications
Change search
Link to record
Permanent link

Direct link
Hausmaninger, Thomas
Publications (10 of 27) Show all publications
Silander, I., Hausmaninger, T., Forssén, C., Zelan, M. & Axner, O. (2019). Gas equilibration gas modulation refractometry for assessment of pressure with sub-ppm precision. Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics, 37(4), Article ID 042901.
Open this publication in new window or tab >>Gas equilibration gas modulation refractometry for assessment of pressure with sub-ppm precision
Show others...
2019 (English)In: Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics, ISSN 2166-2746, E-ISSN 2166-2754, Vol. 37, no 4, article id 042901Article in journal (Refereed) Published
Abstract [en]

Gas modulation refractometry (GAMOR) is a methodology that, by performing repeated reference assessments with the measurement cavity being evacuated while the reference cavity is held at a constant pressure, can mitigate drifts in dual Fabry-Perot cavity based refractometry. A novel realization of GAMOR, referred to as gas equilibration GAMOR, that outperforms the original realization of GAMOR, here referred to as single cavity modulated GAMOR (SCM-GAMOR), is presented. In this, the reference measurements are carried out by equalizing the pressures in the two cavities, whereby the time it takes to reach adequate conditions for the reference measurements has been reduced. This implies that a larger fraction of the measurement cycle can be devoted to data acquisition, which reduces white noise and improves on its short-term characteristics. The presented realization also encompasses a new cavity design with improved temperature stabilization and assessment. This has contributed to improved long-term characteristics of the GAMOR methodology. The system was characterized with respect to a dead weight pressure balance. It was found that the system shows a significantly improved precision with respect to SCM-GAMOR for all integration times. For a pressure of 4303 Pa, it can provide a response for short integration times (up to 10 min) of 1.5 mPa (cycle)1/2, while for longer integration times (up to 18 h), it shows an integration time-independent Allan deviation of 1mPa (corresponding to a precision, defined as twice the Allan deviation, of 0.5 ppm), exceeding the original SCM-GAMOR system by a factor of 2 and 8, respectively. When used for low pressures, it can provide a precision in the sub-mPa region; for the case with an evacuated measurement cavity, the system provided, for up to 40 measurement cycles (ca. 1.5 h), a white noise of 0.7 mPa (cycle)1/2, and a minimum Allan deviation of 0.15mPa. It shows a purely linear response in the 2.8-10.1 kPa range. This implies that the system can be used for the transfer of calibration over large pressure ranges with exceptional low uncertainty.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2019
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:umu:diva-165111 (URN)10.1116/1.5090860 (DOI)000492053600016 ()2-s2.0-85066786025 (Scopus ID)
Available from: 2019-11-13 Created: 2019-11-13 Last updated: 2023-09-07Bibliographically approved
Zhao, G., Hausmaninger, T., Schmidt, F. M., Ma, W. & Axner, O. (2019). High-resolution trace gas detection by sub-Doppler noise-immune cavity-enhanced optical heterodyne molecular spectrometry: application to detection of acetylene in human breath. Optics Express, 27(13), 17940-17953
Open this publication in new window or tab >>High-resolution trace gas detection by sub-Doppler noise-immune cavity-enhanced optical heterodyne molecular spectrometry: application to detection of acetylene in human breath
Show others...
2019 (English)In: Optics Express, E-ISSN 1094-4087, Vol. 27, no 13, p. 17940-17953Article in journal (Refereed) Published
Abstract [en]

A sensitive high-resolution sub-Doppler detecting spectrometer, based on noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS), for trace gas detection of species whose transitions have severe spectral overlap with abundant concomitant species is presented. It is designed around a NICE-OHMS instrumentation utilizing balanced detection that provides shot-noise limited Doppler-broadened (Db) detection. By synchronous dithering the positions of the two cavity mirrors, the effect of residual etalons between the cavity and other surfaces in the system could be reduced. An Allan deviation of the absorption coefficient of 2.2 × 10-13 cm-1 at 60 s, which, for the targeted transition in C2H2, corresponds to a 3σ detection sensitivity of 130 ppt, is demonstrated. It is shown that despite significant spectral interference from CO2 at the targeted transition, which precludes Db detection of C2H2, acetylene could be detected in exhaled breath of healthy smokers.

Place, publisher, year, edition, pages
Optical Society of America, 2019
National Category
Atom and Molecular Physics and Optics Physical Chemistry Medical Engineering
Identifiers
urn:nbn:se:umu:diva-161422 (URN)10.1364/OE.27.017940 (DOI)000472621000043 ()31252745 (PubMedID)2-s2.0-85068037731 (Scopus ID)
Projects
Bio4Energy
Funder
Swedish Research Council, 2015-04374Swedish Research Council, 2013-6031The Kempe Foundations, JCK-1317The Kempe Foundations, SMK-1446Bio4Energy
Available from: 2019-07-07 Created: 2019-07-07 Last updated: 2023-03-23Bibliographically approved
Johansson, A. C., Rutkowski, L., Maslowski, P., Filipsson, A., Hausmaninger, T., Zhao, G., . . . Foltynowicz, A. (2019). Precise comb-based fourier transform spectroscopy for line parameter retrieval. In: 2019 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference (CLEO/EUROPE-EQEC): . Paper presented at Conference on Lasers and Electro-Optics Europe / European Quantum Electronics Conference (CLEO/Europe-EQEC), Munich, GERMANY, JUN 23-27, 2019.. Institute of Electrical and Electronics Engineers (IEEE), Article ID 8872655.
Open this publication in new window or tab >>Precise comb-based fourier transform spectroscopy for line parameter retrieval
Show others...
2019 (English)In: 2019 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference (CLEO/EUROPE-EQEC), Institute of Electrical and Electronics Engineers (IEEE), 2019, article id 8872655Conference paper, Published paper (Refereed)
Abstract [en]

Accurate parameters of molecular transitions are needed for data analysis in many applications, ranging from atmospheric research to astrophysics and determination of fundamental constants. Optical frequency comb Fourier transform spectroscopy (OFC-FTS) is particularly well-suited for high-precision measurements of broadband molecular spectra. From these spectra, the parameters of individual transitions - all measured simultaneously under the same experimental conditions - can be determined. We use a mechanical OFC-FTS spectrometer with sub-nominal resolution [1, 2] to perform precise broadband measurements of entire molecular bands of CO2 using either direct absorption spectroscopy or cavity-enhanced complex refractive index spectroscopy (CE-CRIS) [3] and we extract line parameters for line shapes beyond the Voigt profile.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2019
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:umu:diva-187341 (URN)10.1109/CLEOE-EQEC.2019.8872655 (DOI)000630002700957 ()2-s2.0-85074627170 (Scopus ID)978-1-7281-0469-0 (ISBN)
Conference
Conference on Lasers and Electro-Optics Europe / European Quantum Electronics Conference (CLEO/Europe-EQEC), Munich, GERMANY, JUN 23-27, 2019.
Available from: 2021-09-13 Created: 2021-09-13 Last updated: 2023-08-28Bibliographically approved
Johansson, A. C., Rutkowski, L., Filipsson, A., Hausmaninger, T., Zhao, G., Axner, O. & Foltynowicz, A. (2018). Broadband calibration-free cavity-enhanced complex refractive index spectroscopy using a frequency comb. Optics Express, 26(16), 20633-20648
Open this publication in new window or tab >>Broadband calibration-free cavity-enhanced complex refractive index spectroscopy using a frequency comb
Show others...
2018 (English)In: Optics Express, E-ISSN 1094-4087, Vol. 26, no 16, p. 20633-20648Article in journal (Refereed) Published
Abstract [en]

We present broadband cavity-enhanced complex refractive index spectroscopy (CE-CRIS), a technique for calibration-free determination of the complex refractive index of entire molecular bands via direct measurement of transmission modes of a Fabry-Perot cavity filled with the sample. The measurement of the cavity transmission spectrum is done using an optical frequency comb and a mechanical Fourier transform spectrometer with sub-nominal resolution. Molecular absorption and dispersion spectra (corresponding to the imaginary and real parts of the refractive index) are obtained from the cavity mode broadening and shift retrieved from fits of Lorentzian profiles to the individual cavity modes. This method is calibration-free because the mode broadening and shift are independent of the cavity parameters such as the length and mirror reflectivity. In this first demonstration of broadband CE-CRIS we measure simultaneously the absorption and dispersion spectra of three combination bands of CO2 in the range between 1525 nm and 1620 nm and achieve good agreement with theoretical models. This opens up for precision spectroscopy of the complex refractive index of several molecular bands simultaneously. 

Place, publisher, year, edition, pages
Optical Society of America, 2018
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:umu:diva-151397 (URN)10.1364/OE.26.020633 (DOI)000440803600079 ()30119372 (PubMedID)2-s2.0-85051244198 (Scopus ID)
Funder
Swedish Research Council, 2016-03593Swedish Research Council, 2015-04374Knut and Alice Wallenberg Foundation, KAW 2015.0159
Available from: 2018-09-04 Created: 2018-09-04 Last updated: 2023-03-23Bibliographically approved
Johansson, A. C., Rutkowski, L., Filipsson, A., Hausmaninger, T., Zhao, G., Axner, O. & Foltynowicz, A. (2018). Broadband Complex Refractive Index Spectroscopy via Measurement of Cavity Modes. In: 2018 Conference on Lasers and Electro-Optics (CLEO): . Paper presented at Conference on Lasers and Electro-Optics (CLEO), May 13-18, 2018, San Jose, CA, United States. IEEE
Open this publication in new window or tab >>Broadband Complex Refractive Index Spectroscopy via Measurement of Cavity Modes
Show others...
2018 (English)In: 2018 Conference on Lasers and Electro-Optics (CLEO), IEEE, 2018Conference paper (Refereed)
Abstract [en]

We retrieve high precision absorption and dispersion spectra of the 3v(1)+v(3) band of CO2 from direct measurement of cavity transmission modes using an optical frequency comb and a mechanical Fourier transfolin spectrometer with sub-nominal resolution.

Place, publisher, year, edition, pages
IEEE, 2018
Series
Conference on Lasers and Electro-Optics, ISSN 2160-9020
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:umu:diva-174239 (URN)10.1364/CLEO_SI.2018.STu3P.4 (DOI)000526031003272 ()2-s2.0-85048952198 (Scopus ID)978-1-9435-8042-2 (ISBN)
Conference
Conference on Lasers and Electro-Optics (CLEO), May 13-18, 2018, San Jose, CA, United States
Note

Paper STu3P.4

Available from: 2020-08-19 Created: 2020-08-19 Last updated: 2023-03-24Bibliographically approved
Johansson, A. C., Rutkowski, L., Filipsson, A., Hausmaninger, T., Zhao, G., Axner, O. & Foltynowicz, A. (2018). Cavity-enhanced complex refractive index spectroscopy of entire molecular bands using a frequency comb. In: Optics InfoBase Conference Papers: . Paper presented at Fourier Transform Spectroscopy, FTS 2018, 5–8 November, 2018, Singapore, Singapore. Optica Publishing Group, Article ID JT2A.29.
Open this publication in new window or tab >>Cavity-enhanced complex refractive index spectroscopy of entire molecular bands using a frequency comb
Show others...
2018 (English)In: Optics InfoBase Conference Papers, Optica Publishing Group , 2018, article id JT2A.29Conference paper, Published paper (Refereed)
Abstract [en]

We demonstrate broadband calibration-free complex refractive index spectroscopy of entire molecular bands by direct measurement of transmission modes of a Fabry-Perot cavity using frequency comb-based Fourier transform spectrometer with sub-nominal resolution.

Place, publisher, year, edition, pages
Optica Publishing Group, 2018
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:umu:diva-203021 (URN)10.1364/FTS.2018.JT2A.29 (DOI)2-s2.0-85059542397 (Scopus ID)9781943580477 (ISBN)
Conference
Fourier Transform Spectroscopy, FTS 2018, 5–8 November, 2018, Singapore, Singapore
Available from: 2023-01-16 Created: 2023-01-16 Last updated: 2023-03-24Bibliographically approved
Hausmaninger, T., Zhao, G., Ma, W. & Axner, O. (2018). Depletion of the vibrational ground state of CH4 in absorption spectroscopy at 3.4 μm in N2 and air in the 1-100Torr range. Journal of Quantitative Spectroscopy and Radiative Transfer, 205, 59-70
Open this publication in new window or tab >>Depletion of the vibrational ground state of CH4 in absorption spectroscopy at 3.4 μm in N2 and air in the 1-100Torr range
2018 (English)In: Journal of Quantitative Spectroscopy and Radiative Transfer, ISSN 0022-4073, E-ISSN 1879-1352, Vol. 205, p. 59-70Article in journal (Refereed) Published
Abstract [en]

A model presented in an accompanying work predicts that mid-IR absorption signals from methane in trace concentrations in various buffer gases detected at pressures in the 1-100Torr range can be reduced and distorted due to depletion of the vibrational ground state if the molecules are exposed to laser powers in the tens of mW range or above. This work provides experimental evidence of such depletion in a resonant cavity under a variety of conditions, e.g. for intracavity laser powers up to 2W and for buffer gases of N-2 or dry air, and verifies the applicability of the model. It was found that the degree of depletion is significantly larger in N-2 than dry air, and that it increases with pressure for pressures up to around 10Torr (attributed to a decreased diffusion rate) but decreases with pressure for pressures above 20Torr (caused by an increased collisional vibrational decay rate). The maximum degree of depletion (similar to 80%) was obtained for methane in N-2 at around 15Torr. This implies that absorption spectrometry of methane can experience significant non-linear dependencies on laser power, pressure, as well as buffer gas composition. It is shown that depletion takes place also in (CH4)-C-13, which verifies the applicability of the model also for this isotopologue, and that NICE-OHMS signals detected in absorption phase are less affected by depletion than in dispersion. It was concluded that the absorption mode of detection can provide concentration assessments that are virtually free of influence of depletion for intracavity powers below 0.8 W. 

Place, publisher, year, edition, pages
PERGAMON-ELSEVIER SCIENCE LTD, 2018
Keywords
Absorption spectroscopy, Cavity enhanced, Noise-immune cavity-enhanced optical heterodyne molecular spectroscopy, Methane, Depletion, Optical saturation
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:umu:diva-143714 (URN)10.1016/j.jqsrt.2017.10.007 (DOI)000417665000008 ()2-s2.0-85033558806 (Scopus ID)
Available from: 2018-01-08 Created: 2018-01-08 Last updated: 2023-03-24Bibliographically approved
Silander, I., Hausmaninger, T., Zelan, M. & Axner, O. (2018). Gas modulation refractometry for high-precision assessment of pressure under non-temperature-stabilized conditions. Paper presented at AVS 64th International Symposium and Exhibition, OCT 29-NOV 03, 2017, Tampa, FL, USA. Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, 36(3), Article ID 03E105.
Open this publication in new window or tab >>Gas modulation refractometry for high-precision assessment of pressure under non-temperature-stabilized conditions
2018 (English)In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 36, no 3, article id 03E105Article in journal (Refereed) Published
Abstract [en]

The authors report on the realization of a novel methodology for refractometry-GAs modulation refractometry (GAMOR)-that decreases the influence of drifts in Fabry Perot cavity refractometry. The instrumentation is based on a dual Fabry-Perot cavity refractometer in which the beat frequency between the light fields locked to two different cavities, one measurement and one reference cavity, is measured. The GAMOR methodology comprises a process in which the measurement cavity sequentially is filled and evacuated while the reference cavity is constantly evacuated. By performing beat frequency measurements both before and after the finite-pressure measurement, zero point references are periodically created. This opens up for high precision refractometry under nontemperature-stabilized conditions. A first version of an instrumentation based on the GAMOR methodology has been realized and its basic performance has been scrutinized. The refractometer consists of a Zerodur cavity-block and tunable narrow linewidth fiber lasers operating within the C34 communication channel (i.e., around 1.55 μm) at which there are a multitude of fiber coupled off-the-shelf optical, electro-optic, and acousto-optic components. The system is fully computer controlled, which implies it can perform unattended gas assessments over any foreseeable length of time. When applied to a system with no active temperature stabilization, the GAMOR methodology has demonstrated a 3 orders of magnitude improvement of the precision with respect to conventional static detection. When referenced to a dead weight pressure scale the instrumentation has demonstrated assessment of pressures in the kilo-Pascal range (4303 and 7226 Pa) limited by white noise with standard deviations in the 3.2N-1/2-3.5N-1/2 mPa range, where N is the number of measurement cycles (each being 100 s long). For short measurement times (up to around 103 s), the system exhibits a (1σ) total relative precision of 0.7 (0.5) ppm for assessment of pressures in the 4 kPa region and 0.5 (0.4) ppm for pressures around 7 kPa, where the numbers in parentheses represent the part of the total noise that has been attributed to the refractometer. As long as the measurement procedure is performed over short time scales, the inherent properties of the GAMOR methodology allow for high precision assessments by the use of instrumentation that is not actively temperature stabilized or systems that are affected by outgassing or leaks. They also open up for a variety of applications within metrology; e.g., transfer of calibration and characterization of pressure gauges, including piston gauges.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2018
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:umu:diva-148832 (URN)10.1116/1.5022244 (DOI)000432372400005 ()2-s2.0-85045843634 (Scopus ID)
Conference
AVS 64th International Symposium and Exhibition, OCT 29-NOV 03, 2017, Tampa, FL, USA
Available from: 2018-06-13 Created: 2018-06-13 Last updated: 2023-09-07Bibliographically approved
Hausmaninger, T. (2018). Mid- and near-infrared NICE-OHMS: techniques for ultra-sensitive detection of molecules in gas phase. (Doctoral dissertation). Umeå: Umeå universitet
Open this publication in new window or tab >>Mid- and near-infrared NICE-OHMS: techniques for ultra-sensitive detection of molecules in gas phase
2018 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) is a technique for ultra-sensitive detection of molecular absorption and dispersion. For highest performance, the technique combines cavity enhancement (CE) with frequency modulation (FM); while the former increases the effective interaction length between the light and the analyte by several orders of magnitudes, the latter removes the in-coupling of 1/f noise and makes the signals background free. The combination of CE and FM also gives the technique an immunity to amplitude noise caused by the jitter of the laser frequency relative to the cavity resonance frequencies. All these properties make the technique suitable for ultra sensitive trace gas detection in the sub-parts-per-trillion (ppt) range. The aim of this thesis is to improve the performance of the NICE-OHMS technique and to increase its range of applications.

The work in this thesis can be divided into three areas:Firstly, a mid-infrared (MIR)-NICE-OHMS instrumentation was developed. In a first realization an unprecedented white-noise equivalent absorption limit for Doppler broadened (Db) detection in the MIR of 3×10-9 cm-1Hz-1/2was demonstrated. This was subsequently improved to 2.4×10-10 cm-1Hz-1/2allowing for detection methane and its two main isotopologues (CH3D and 13CH4) at their natural abundance.Secondly, further development of an existing near-infrared NICE-OHMS system was performed. This resulted in an improved longtime stability and the first shot-noise limited NICE-OHMS system for Db detection with a noise equivalent absorption limit of 2.3×10-14 cm-1detected over 200 s. Thirdly, models and theoretical descriptions of NICE-OHMS signals under strong absorption conditions and from methane under high laser power were developed. It was experimentally verified that the models allow for a more accurate evaluation of NICE-OHMS signals under a wide range of conditions.

Abstract [sv]

Brusimmun kavitetsförstärkt optisk-heterodyndetekterad molekylärspektroskopi (eng.Noise-immune cavity-enhanced optical heterodyne molecular spectrometry, NICE-OHMS) är en teknik för ultrakänslig detektion av molekylär absorption och dispersion. NICE-OHMS-tekniken kombinerar kavitetsförstärkning (eng. CE) med frekvensmodulering (FM); emedan den första väsentligt ökar den effektiva interaktionslängden mellan ljuset och analyten vilket ökar teknikens känslighet, tar den senare bort inkopplingen av 1/f-brus och gör signalerna bakgrundsfria. Kombinationen av CE och FM ger också tekniken en immunitet mot amplitudstörning som orsakas av jitter hos laserljusets frekvens i förhållande till kavitetsresonansfrekvenserna. Alla dessa egenskaper gör tekniken lämplig för ultrakänslig spårgasdetektering i och under ppt (eng. parts-per-trillion) - området. Syftet med denna avhandling är att förbättra prestandan hos NICE-OHMS-tekniken och att öka dess tillämpningspotential.

Avhandlingen kan delas in i tre delar: Inom den första utvecklades en mid-infraröd (MIR)-NICE-OHMS instrumentering. Vid en första realisering påvisades en aldrig tidigare uppnådd vitt-brus-ekvivalent absorptionsgräns för Dopplerbreddad (Db) detektering i MIR området på 3 × 10-9 cm-1Hz-1/2. Detta förbättrades därefter till 2,4 x 10-10 cm-1Hz-1/2, vilket möjliggör detektering av metan och dess två huvudsakliga isotopologer (CH3D och 13CH4) vid deras naturliga förekomst. Inom det andra området utfördes vidareutveckling av ett existerande NICE-OHMS-system verksamt i det när-infraröda (NIR) området. Detta resulterade i en förbättrad långtidsstabilitet och en brus-ekvivalent absorptionsgräns för Db detektion på 2,3 × 10-14 cm-1 mätt över 200 s. Inom den tredje utvecklades modeller och teoretiska beskrivningar av NICE-OHMS under starka absorptionsförhållanden och från metan under hög laserintensitet. Det var experimentellt verifierat att modellerna möjliggör en mer noggrann utvärdering av NICE-OHMS-signalerunder ett stort antal förhållanden.

Place, publisher, year, edition, pages
Umeå: Umeå universitet, 2018. p. 139
Keywords
spectrometry, NICE-OHMS, trace gas detection, acetylene, methane, isotopologues, near-infrared, mid-infrared, shot-noise, optical parametric oscillator
National Category
Atom and Molecular Physics and Optics
Research subject
engineering science with specialization in microsystems technology
Identifiers
urn:nbn:se:umu:diva-153068 (URN)978-91-7601-977-1 (ISBN)
Public defence
2018-11-30, N450, Naturvetarhuset, Umeå, 10:00 (English)
Opponent
Supervisors
Available from: 2018-11-09 Created: 2018-11-06 Last updated: 2018-11-13Bibliographically approved
Zhao, G., Hausmaninger, T., Ma, W. & Axner, O. (2018). Shot-noise-limited Doppler-broadened noise-immune cavity-enhanced optical heterodyne molecular spectrometry. Optics Letters, 43(4), 715-718
Open this publication in new window or tab >>Shot-noise-limited Doppler-broadened noise-immune cavity-enhanced optical heterodyne molecular spectrometry
2018 (English)In: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 43, no 4, p. 715-718Article in journal (Refereed) Published
Abstract [en]

Shot-noise-limited Doppler-broadened (Db) noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) has been realized by implementation of balanced detection. A characterization of the system based on Allan-Werle plots of the absorption coefficient, retrieved by fitting a model function to data, shows that the system has a white noise equivalent absorption per unit length per square root of bandwidth of 2.3 x 10(-13) cm(-1) Hz(-1/2), solely 44% above the shot noise limit, and a detection sensitivity of 2.2 x 10(-14) cm(-1) over 200 s, both being unprecedented for Db NICE-OHMS. The white noise response follows the expected inverse square root dependence on power that is representative of a shot-noise-limited response, which confirms that the system is shot-noise-limited. 

National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:umu:diva-145590 (URN)10.1364/OL.43.000715 (DOI)000425123700023 ()29444060 (PubMedID)2-s2.0-85042053622 (Scopus ID)
Funder
Swedish Research Council, 2015-04374
Available from: 2018-03-21 Created: 2018-03-21 Last updated: 2023-03-23Bibliographically approved
Organisations

Search in DiVA

Show all publications