TY  - JOUR
AU  - Davidović, Ljubica D.
AU  - Arsenović, Dušan
AU  - Davidović, Milena
AU  - Davidović, Dragomir M.
PY  - 2009
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/269
AB  - Using the resolution of identity spanned by coherent states of the harmonic oscillator, any entire function of the creation and the annihilation operators and its action on a vector in Hilbert space can be defined directly and simply. We show that such a direct approach applied to non-entire functions ln (a) over cap and ln (a) over cap (dagger), present in the literature, may lead to errors and contradictions. We elucidate their roots and propose a way to avoid them. We discuss the obtained results.
T2  - Journal of Physics A-Mathematical and Theoretical
T1  - Subtle inconsistencies in the straightforward definition of the logarithmic function of annihilation and creation operators and a way to avoid them
IS  - 23
VL  - 42
DO  - 10.1088/1751-8113/42/23/235302
ER  - 

@article{
author = "Davidović, Ljubica D. and Arsenović, Dušan and Davidović, Milena and Davidović, Dragomir M.",
year = "2009",
abstract = "Using the resolution of identity spanned by coherent states of the harmonic oscillator, any entire function of the creation and the annihilation operators and its action on a vector in Hilbert space can be defined directly and simply. We show that such a direct approach applied to non-entire functions ln (a) over cap and ln (a) over cap (dagger), present in the literature, may lead to errors and contradictions. We elucidate their roots and propose a way to avoid them. We discuss the obtained results.",
journal = "Journal of Physics A-Mathematical and Theoretical",
title = "Subtle inconsistencies in the straightforward definition of the logarithmic function of annihilation and creation operators and a way to avoid them",
number = "23",
volume = "42",
doi = "10.1088/1751-8113/42/23/235302"
}

Davidović, L. D., Arsenović, D., Davidović, M.,& Davidović, D. M.. (2009). Subtle inconsistencies in the straightforward definition of the logarithmic function of annihilation and creation operators and a way to avoid them. in Journal of Physics A-Mathematical and Theoretical, 42(23).
https://doi.org/10.1088/1751-8113/42/23/235302

Davidović LD, Arsenović D, Davidović M, Davidović DM. Subtle inconsistencies in the straightforward definition of the logarithmic function of annihilation and creation operators and a way to avoid them. in Journal of Physics A-Mathematical and Theoretical. 2009;42(23).
doi:10.1088/1751-8113/42/23/235302 .

Davidović, Ljubica D., Arsenović, Dušan, Davidović, Milena, Davidović, Dragomir M., "Subtle inconsistencies in the straightforward definition of the logarithmic function of annihilation and creation operators and a way to avoid them" in Journal of Physics A-Mathematical and Theoretical, 42, no. 23 (2009),
https://doi.org/10.1088/1751-8113/42/23/235302 . .

TY  - JOUR
AU  - Davidović, Milos D.
AU  - Davidović, Milena
PY  - 2009
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/239
AB  - To better elucidate the essential energy transmission Mechanism in the most common, typical waveguides, the electromagnetic energy flow lines for a planar optical slab waveguide and a microwave rectangular waveguide are constructed. The obtained results supply more direct and transparent insight into the distribution of electromagnetic energy in the modes of various character.
T2  - Acta Physica Polonica A
T1  - Mode Analysis of the Optical and the Microwave Waveguides Using Electromagnetic Energy Flow Lines
EP  - 674
IS  - 4
SP  - 672
VL  - 116
UR  - https://hdl.handle.net/21.15107/rcub_grafar_239
ER  - 

@article{
author = "Davidović, Milos D. and Davidović, Milena",
year = "2009",
abstract = "To better elucidate the essential energy transmission Mechanism in the most common, typical waveguides, the electromagnetic energy flow lines for a planar optical slab waveguide and a microwave rectangular waveguide are constructed. The obtained results supply more direct and transparent insight into the distribution of electromagnetic energy in the modes of various character.",
journal = "Acta Physica Polonica A",
title = "Mode Analysis of the Optical and the Microwave Waveguides Using Electromagnetic Energy Flow Lines",
pages = "674-672",
number = "4",
volume = "116",
url = "https://hdl.handle.net/21.15107/rcub_grafar_239"
}

Davidović, M. D.,& Davidović, M.. (2009). Mode Analysis of the Optical and the Microwave Waveguides Using Electromagnetic Energy Flow Lines. in Acta Physica Polonica A, 116(4), 672-674.
https://hdl.handle.net/21.15107/rcub_grafar_239

Davidović MD, Davidović M. Mode Analysis of the Optical and the Microwave Waveguides Using Electromagnetic Energy Flow Lines. in Acta Physica Polonica A. 2009;116(4):672-674.
https://hdl.handle.net/21.15107/rcub_grafar_239 .

Davidović, Milos D., Davidović, Milena, "Mode Analysis of the Optical and the Microwave Waveguides Using Electromagnetic Energy Flow Lines" in Acta Physica Polonica A, 116, no. 4 (2009):672-674,
https://hdl.handle.net/21.15107/rcub_grafar_239 .

TY  - JOUR
AU  - Davidović, Milos D.
AU  - Davidović, Milena
AU  - Vojisavljević, Vuk
PY  - 2009
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/237
AB  - Time-frequency analysis is important to identify the localized information of a non-stationary signal in the time and frequency domains simultaneously. There are few different time-frequency analysis methods available with their own specialty and suitability. In quantum mechanics Husimi function of any quantum mechanical state arises naturally whenever the simultaneous measurement of both coordinate and momentum is performed on this state with maximal accuracy allowed by the Heisenberg uncertainty relations. The Husimi function is a probability distribution for the statistics of simultaneous unsharp measurement of both coordinate and momentum. In general, like the Wigner function, the Husimi function can be defined in the space of any pair of conjugate variables. In particular, in the studies of signal processing, this space is the time-frequency space. In the present work we consider the Husimi function in this space, and apply it to analyse the multicomponent signals. The time-frequency representations of the simulated signals by using the Husimi distribution clearly show the frequency features along the time axis. The results are encouraging and indicate that, like in corresponding analogous problems in quantum mechanics, the Husimi distribution approach in the time-frequency analysis for non-stationary optical signals may provide some insights which are not so easily obtained in other, more spread approaches.
PB  - Polish Academy of Sciences
T2  - Acta Physica Polonica A
T1  - Time-Frequency Analysis of Nonstationary Optical Signals Using Husimi Type Function
EP  - 677
IS  - 4
SP  - 675
VL  - 116
DO  - 10.12693/APhysPolA.116.675
ER  - 

@article{
author = "Davidović, Milos D. and Davidović, Milena and Vojisavljević, Vuk",
year = "2009",
abstract = "Time-frequency analysis is important to identify the localized information of a non-stationary signal in the time and frequency domains simultaneously. There are few different time-frequency analysis methods available with their own specialty and suitability. In quantum mechanics Husimi function of any quantum mechanical state arises naturally whenever the simultaneous measurement of both coordinate and momentum is performed on this state with maximal accuracy allowed by the Heisenberg uncertainty relations. The Husimi function is a probability distribution for the statistics of simultaneous unsharp measurement of both coordinate and momentum. In general, like the Wigner function, the Husimi function can be defined in the space of any pair of conjugate variables. In particular, in the studies of signal processing, this space is the time-frequency space. In the present work we consider the Husimi function in this space, and apply it to analyse the multicomponent signals. The time-frequency representations of the simulated signals by using the Husimi distribution clearly show the frequency features along the time axis. The results are encouraging and indicate that, like in corresponding analogous problems in quantum mechanics, the Husimi distribution approach in the time-frequency analysis for non-stationary optical signals may provide some insights which are not so easily obtained in other, more spread approaches.",
publisher = "Polish Academy of Sciences",
journal = "Acta Physica Polonica A",
title = "Time-Frequency Analysis of Nonstationary Optical Signals Using Husimi Type Function",
pages = "677-675",
number = "4",
volume = "116",
doi = "10.12693/APhysPolA.116.675"
}

Davidović, M. D., Davidović, M.,& Vojisavljević, V.. (2009). Time-Frequency Analysis of Nonstationary Optical Signals Using Husimi Type Function. in Acta Physica Polonica A
Polish Academy of Sciences., 116(4), 675-677.
https://doi.org/10.12693/APhysPolA.116.675

Davidović MD, Davidović M, Vojisavljević V. Time-Frequency Analysis of Nonstationary Optical Signals Using Husimi Type Function. in Acta Physica Polonica A. 2009;116(4):675-677.
doi:10.12693/APhysPolA.116.675 .

Davidović, Milos D., Davidović, Milena, Vojisavljević, Vuk, "Time-Frequency Analysis of Nonstationary Optical Signals Using Husimi Type Function" in Acta Physica Polonica A, 116, no. 4 (2009):675-677,
https://doi.org/10.12693/APhysPolA.116.675 . .