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Absolute Sensitivity
The Experts below are selected from a list of 228 Experts worldwide ranked by ideXlab platform
Weiping Zhang – One of the best experts on this subject based on the ideXlab platform.
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Absolute Sensitivity of phase measurement in an su 1 1 type interferometer
Optics Letters, 2018Co-Authors: Jun Jia, J F Chen, Weiping ZhangAbstract:Absolute Sensitivity is measured for the phase measurement in an SU(1,1) type interferometer, and the results are compared to that of a Mach–Zehnder interferometer operated under the condition of the same intra-interferometer intensity. The interferometer is phase locked to a point with the largest quantum noise cancellation, and a simulated phase modumodulation is added in one arm of the SU(1,1) interferometer. Both the signal and noise level are estimated at the same frequency range, and we obtained 3 dB improvement in Sensitivity for the SU(1,1) interferometer over the Mach–Zehnder interferometer. Our results demonstrate a direct phase estimation and may pave the way for practical applications of a nonlinear interferometer.
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Absolute Sensitivity of phase measurement in an su 1 1 type interferometer
arXiv: Quantum Physics, 2017Co-Authors: Jun Jia, J F Chen, Weiping ZhangAbstract:Absolute Sensitivity is measured for the phase measurement in an SU(1,1) type interferometer and the results are compared to that of a Mach-Zehnder inteinterferometer operated under the condition of the same intra-interferometer intensity. The interferometer is phase locked to a point with the largest quantum noise cancellation, and a simulated phase modumodulation is added in one arm of SU(1,1) interferometer. Both the signal and noise level are estimated at the same frequency range, and we obtain 3dB improvement in Sensitivity for the SU(1,1) interferometer over the Mach-Zehnder inteinterferometer. Our results demonstrate a direct phase estimation, and may pave the way for practical applications of nonlinear interferometer.
Weixiong You – One of the best experts on this subject based on the ideXlab platform.
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A universal strategy to enhance the Absolute Sensitivity for temperature detection in bright Er3+/Yb3+ doped double perovskite Gd2ZnTiO6 phosphors
Materials Chemistry Frontiers, 2020Co-Authors: Zhongliang Xiao, Fengqin Lai, Jianhui Huang, Weixiong YouAbstract:The Absolute Sensitivity as a crucial parameter in temperature detection applications is affected by the fluorescence intensity ratio (FIR) of thermally coupled levels (TCLs), whereas no universal research on the utilization of the FIR effect has been performed to rationally achieve high Absolute Sensitivity. Herein, a universal strategy on the manipulation of the FIR effect is put forward for the first time. In the Er3+-activated Gd2ZnTiO6 (GZT) system, the maximum Absolute Sensitivity of 218.8 × 10−4 K−1 at 313 K is obtained based on this strategy in the 2H11/2–4S3/2 group, which is enhanced by a factor of 4.6 relative to its original maximum Absolute Sensitivity. Provably, the maximum Absolute Sensitivity of 398.7 × 10−4 K−1 at 313 K in the 2H11/2–4S3/2 group is gained in the Er3+-activated NaYF4 material, which is enhanced by a factor of 12.3. Such high Absolute Sensitivity is unprecedented in fluoride upconversion (UC) materials. Besides, high Sensitivity and excellent UC emissions suggest that the Er3+-activated GZT material may be a candidate for temperature detection. This work offers a universal strategy to enhance the Absolute Sensitivity and maintain the relative Sensitivity and opens a new perspective for the development of temperature detection.
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a universal strategy to enhance the Absolute Sensitivity for temperature detection in bright er3 yb3 doped double perovskite gd2zntio6 phosphors
Materials Chemistry Frontiers, 2020Co-Authors: Zhongliang Xiao, Fengqin Lai, Jianhui Huang, Weixiong YouAbstract:The Absolute Sensitivity as a crucial parameter in temperature detection applications is affected by the fluorescence intensity ratio (FIR) of thermally coupled levels (TCLs), whereas no universal research on the utilization of the FIR effect has been performed to rationally achieve high Absolute Sensitivity. Herein, a universal strategy on the manipulation of the FIR effect is put forward for the first time. In the Er3+-activated Gd2ZnTiO6 (GZT) system, the maximum Absolute Sensitivity of 218.8 × 10−4 K−1 at 313 K is obtained based on this strategy in the 2H11/2–4S3/2 group, which is enhanced by a factor of 4.6 relative to its original maximum Absolute Sensitivity. Provably, the maximum Absolute Sensitivity of 398.7 × 10−4 K−1 at 313 K in the 2H11/2–4S3/2 group is gained in the Er3+-activated NaYF4 material, which is enhanced by a factor of 12.3. Such high Absolute Sensitivity is unprecedented in fluoride upconversion (UC) materials. Besides, high Sensitivity and excellent UC emissions suggest that the Er3+-activated GZT material may be a candidate for temperature detection. This work offers a universal strategy to enhance the Absolute Sensitivity and maintain the relative Sensitivity and opens a new perspective for the development of temperature detection.
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Crucial processes for upconversion white emission and ultrahigh Sensitivity in Er3+/Tm3+/Yb3+ tri-doped double perovskite Gd2ZnTiO6 phosphors
Optical Materials, 2020Co-Authors: Zongliang Xiao, Jianhui Huang, Fengqin Lai, Weixiong YouAbstract:Abstract Upconversion (UC) luminescence properties are of great significance in realizing good performances on practical display and sensing applications and that can be tuned by adjusting UC energy transfer (ET) processes. In this work, we devoted to gaining UC white emission and achieving high sensing Sensitivity by manipulating ET processes in the Er3+/Tm3+/Yb3+ tri-doped double perovskite Gd2ZnTiO6 (GZT) phosphors. Nearly standard UC white emission with the CIE coordinate of (0.333, 0.331) was obtained based on effective ET processes between Er3+, Tm3+ and Yb3+ in the GZT: 0.5%Er3+/3.5%Tm3+/15%Yb3+ sample. The maximum Absolute Sensitivity of 5.02 K-1 (473 K) of non-thermally coupled levels ( I 635 − 685 ∕ I 500 − 540 ) and another the maximum Absolute Sensitivity of 84.6 × 10−4 K−1 (473 K) of thermally coupled levels ( I 500 − 540 ∕ I 540 − 600 ) were gained. The two Absolute sensitivities both are higher than that in Tm3+/Yb3+ and Er3+/Yb3+ co-doped double perovskite GZT phosphors, respectively. The enhancements of sensitivities are due to the effective ET processes between Er3+, Tm3+ and Yb3+. This work reveals not only certified UC processes for UC white emission but also a valid idea on the manipulation of UC processes towards high Absolute Sensitivity in phosphors.
Gael De Paepe – One of the best experts on this subject based on the ideXlab platform.
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MAS-DNP Enhancements: Hyperpolarization, Depolarization, and Absolute Sensitivity
eMagRes, 2018Co-Authors: Sabine Hediger, Daniel Lee, Frederic Mentink-vigier, Gael De PaepeAbstract:Dynamic nuclear polarization at high magnetic fields has made significant progress over the last decades, and this hyperpolarizing technique is currently revolutionizing the impact of solid-state NMR for the study of complex systems in chemistry, material science, and biology. In this article, we emphasize the importance and difficulty in quantifying Sensitivity from DNP under magic-angle spinning. To this end, we provide insight into the cross effect, the current main MAS-DNP mechanism. This includes a description of the microwave-induced hyperpolarization phenomenon but also of the reduction of the NMR signal prior to microwave irradiation for samples doped with polarizing agents (bleaching and depolarization effects). We highlight the importance of the nuclear hyperpolarization buildup time in the evaluation of MAS-DNP efficiency. Finally, we discuss other experimental parameters affecting Sensitivity in DNP-enhanced spectra and propose a guideline for its proper characterization depending on the type of investigation.
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nuclear depolarization and Absolute Sensitivity in magic angle spinning cross effect dynamic nuclear polarization
Physical Chemistry Chemical Physics, 2015Co-Authors: Frederic Mentinkvigier, Sabine Hediger, Subhradip Paul, Akiva Feintuch, Shimon Vega, Gael De PaepeAbstract:Over the last two decades solid state Nuclear Magnetic ResoResonance has witnessed a breakthrough in increasing the nuclear polarization, and thus experimental Sensitivity, with the advent of Magic Angle Spinning Dynamic Nuclear Polarization (MAS-DNP). To enhance the nuclear polarization of protons, exogenous nitroxide biradicals such as TOTAPOL or AMUPOL are routinely used. Their efficiency is usually assessed as the ratio between the NMR signsignal intensity in the presence and the absence of microwave irradiation eon/off. While TOTAPOL delivers an enhancement eon/off of about 60 on a model sample, the more recent AMUPOL is more efficient: >200 at 100 K. Such a comparison is valid as long as the signal measured in the absence of microwaves is merely the Boltzmann polarization and is not affected by the spinning of the sample. However, recent MAS-DNP studies at 25 K by Thurber and Tycko (2014) have demonstrated that the presence of nitroxide biradicals combined with sample spinning can lead to a depolarized nuclear state, below the Boltzmann polarization. In this work we demonstrate that TOTAPOL and AMUPOL both lead to observable depolarization at ≈110 K, and that the magnitude of this depolarization is radical dependent. Compared to the static sample, TOTAPOL and AMUPOL lead, respectively, to nuclear polarization losses of up to 20% and 60% at a 10 kHz MAS frequency, while Trityl OX63 does not depolarize at all. This experimental work is analyzed using a theoretical model that explains how the depolarization process works under MAS and gives new insights into the DNP mechanism and into the spin parameters, which are relevant for the efficiency of a biradical. In light of these results, the outstanding performance of AMUPOL must be revised and we propose a new method to assess the polarization gain for future radicals.
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Nuclear depolarization and Absolute Sensitivity in magic-angle spinning cross effect dynamic nuclear polarization
Physical Chemistry Chemical Physics, 2015Co-Authors: Frederic Mentink-vigier, Daniel Lee, Sabine Hediger, Subhradip Paul, Akiva Feintuch, Shimon Vega, Gael De PaepeAbstract:Over the last two decades solid state Nuclear Magnetic ResoResonance has witnessed a breakthrough in increasing the nuclear polarization, and thus experimental Sensitivity, with the advent of Magic Angle Spinning Dynamic Nuclear Polarization (MAS-DNP). To enhance the nuclear polarization of protons, exogenous nitroxide biradicals such as TOTAPOL or AMUPOL are routinely used. Their efficiency is usually assessed as the ratio between the NMR signsignal intensity in the presence and the absence of microwave irradiation epsilon(on/off). While TOTAPOL delivers an enhancement epsilon(on/off) of about 60 on a model sample, the more recent AMUPOL is more efficient: >200 at 100 K. Such a comparison is valid as long as the signal measured in the absence of microwaves is merely the Boltzmann polarization and is not affected by the spinning of the sample. However, recent MAS-DNP studies at 25 K by Thurber and Tycko (2014) have demonstrated that the presence of nitroxide biradicals combined with sample spinning can lead to a depolarized nuclear state, below the Boltzmann polarization. In this work we demonstrate that TOTAPOL and AMUPOL both lead to observable depolarization at approximate to 110 K, and that the magnitude of this depolarization is radical dependent. Compared to the static sample, TOTAPOL and AMUPOL lead, respectively, to nuclear polarization losses of up to 20% and 60% at a 10 kHz MAS frequency, while Trityl OX63 does not depolarize at all. This experimental work is analyzed using a theoretical model that explains how the depolarization process works under MAS and gives new insights into the DNP mechanism and into the spin parameters, which are relevant for the efficiency of a biradical. In light of these results, the outstanding performance of AMUPOL must be revised and we propose a new method to assess the polarization gain for future radicals.
Jun Jia – One of the best experts on this subject based on the ideXlab platform.
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Absolute Sensitivity of phase measurement in an su 1 1 type interferometer
Optics Letters, 2018Co-Authors: Jun Jia, J F Chen, Weiping ZhangAbstract:Absolute Sensitivity is measured for the phase measurement in an SU(1,1) type interferometer, and the results are compared to that of a Mach–Zehnder interferometer operated under the condition of the same intra-interferometer intensity. The interferometer is phase locked to a point with the largest quantum noise cancellation, and a simulated phase modulation is added in one arm of the SU(1,1) interferometer. Both the signal and noise level are estimated at the same frequency range, and we obtained 3 dB improvement in Sensitivity for the SU(1,1) interferometer over the Mach–Zehnder interferometer. Our results demonstrate a direct phase estimation and may pave the way for practical applications of a nonlinear interferometer.
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Absolute Sensitivity of phase measurement in an su 1 1 type interferometer
arXiv: Quantum Physics, 2017Co-Authors: Jun Jia, J F Chen, Weiping ZhangAbstract:Absolute Sensitivity is measured for the phase measurement in an SU(1,1) type interferometer and the results are compared to that of a Mach-Zehnder interferometer operated under the condition of the same intra-interferometer intensity. The interferometer is phase locked to a point with the largest quantum noise cancellation, and a simulated phase modulation is added in one arm of SU(1,1) interferometer. Both the signal and noise level are estimated at the same frequency range, and we obtain 3dB improvement in Sensitivity for the SU(1,1) interferometer over the Mach-Zehnder interferometer. Our results demonstrate a direct phase estimation, and may pave the way for practical applications of nonlinear interferometer.
Hans Maaswinkel – One of the best experts on this subject based on the ideXlab platform.
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Visual Sensitivity And Signal Processing In Teleosts
Fish Physiology, 2006Co-Authors: Hans MaaswinkelAbstract:Publisher Summary Fish have adapted to a wide range of habitats, including estuaries, deep sea, lakes, and caves. Accordingly, the characteristics of the visual system vary considerably among species. This chapter presents the research carried out in a small number of species belonging to the cyprinids, such as goldfish ( Carassius auratus ) and zebrafish ( Danio rerio ). Visual Sensitivity can be analyzed along three dimensions: Absolute, contrast, and spectral Sensitivity. The chapter focuses on Absolute Sensitivity. It describes the characteristics of the visual system in teleost fish and presents current research about Absolute visual Sensitivity. Circadian modulation of Absolute Sensitivity and the roles of neurotransmitters, such as dopamine and melatonin are described. The chapter also describes some of the factors that may impair Absolute Sensitivity. When assessing Absolute, contrast, or spectral visual Sensitivity, one has to distinguish the level of processing. Visual sensitivities, as determined by photon catch, electroretinogram (ERG) or retinal ganglion cells (RGC) recordings, or behavioral escape responses, optomotor response (OMR), optokinetic response (OKR), are different parameters that do not always correlate.