TY  - CONF
AU  - Petrovic, Marija
AU  - Petrović, Jovana S.
AU  - Simic, Goran
AU  - Ilic, Igor
AU  - Daničić, Aleksandar
AU  - Vukcevic, Miodrag
AU  - Bojović, Boško
AU  - Hadžievski, Ljupčo
AU  - Allsop, Thomas P.
AU  - Webb, David J.
PY  - 2013
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7036
AB  - Respiratory-volume monitoring is an indispensable part of mechanical ventilation. Here we present a new method of the respiratory-volume measurement based on a single fibre-optical long-period sensor of bending and the correlation between torso curvature and lung volume. Unlike the commonly used air-flow based measurement methods the proposed sensor is drift-free and immune to air-leaks. In the paper, we explain the working principle of sensors, a two-step calibration-test measurement procedure and present results that establish a linear correlation between the change in the local thorax curvature and the change of the lung volume. We also discuss the advantages and limitations of these sensors with respect to the current standards.
T1  - A New Method for Respiratory-Volume Monitoring Based on Long-Period Fibre Gratings
SP  - 2660
EP  - 2663
UR  - https://hdl.handle.net/21.15107/rcub_vinar_7036
ER  - 

@conference{
author = "Petrovic, Marija and Petrović, Jovana S. and Simic, Goran and Ilic, Igor and Daničić, Aleksandar and Vukcevic, Miodrag and Bojović, Boško and Hadžievski, Ljupčo and Allsop, Thomas P. and Webb, David J.",
year = "2013",
abstract = "Respiratory-volume monitoring is an indispensable part of mechanical ventilation. Here we present a new method of the respiratory-volume measurement based on a single fibre-optical long-period sensor of bending and the correlation between torso curvature and lung volume. Unlike the commonly used air-flow based measurement methods the proposed sensor is drift-free and immune to air-leaks. In the paper, we explain the working principle of sensors, a two-step calibration-test measurement procedure and present results that establish a linear correlation between the change in the local thorax curvature and the change of the lung volume. We also discuss the advantages and limitations of these sensors with respect to the current standards.",
title = "A New Method for Respiratory-Volume Monitoring Based on Long-Period Fibre Gratings",
pages = "2660-2663",
url = "https://hdl.handle.net/21.15107/rcub_vinar_7036"
}

Petrovic, M., Petrović, J. S., Simic, G., Ilic, I., Daničić, A., Vukcevic, M., Bojović, B., Hadžievski, L., Allsop, T. P.,& Webb, D. J.. (2013). A New Method for Respiratory-Volume Monitoring Based on Long-Period Fibre Gratings. , 2660-2663.
https://hdl.handle.net/21.15107/rcub_vinar_7036

Petrovic M, Petrović JS, Simic G, Ilic I, Daničić A, Vukcevic M, Bojović B, Hadžievski L, Allsop TP, Webb DJ. A New Method for Respiratory-Volume Monitoring Based on Long-Period Fibre Gratings. 2013;:2660-2663.
https://hdl.handle.net/21.15107/rcub_vinar_7036 .

Petrovic, Marija, Petrović, Jovana S., Simic, Goran, Ilic, Igor, Daničić, Aleksandar, Vukcevic, Miodrag, Bojović, Boško, Hadžievski, Ljupčo, Allsop, Thomas P., Webb, David J., "A New Method for Respiratory-Volume Monitoring Based on Long-Period Fibre Gratings" (2013):2660-2663,
https://hdl.handle.net/21.15107/rcub_vinar_7036 .

TY  - JOUR
AU  - Beličev, Petra
AU  - Ilic, Igor
AU  - Stepić, Milutin
AU  - Hadžievski, Ljupčo
AU  - Lou, Cibo
AU  - Suntsov, Sergiy
AU  - Rueter, Christian E.
AU  - Kip, Detlef
PY  - 2013
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5648
AB  - We observe theoretically and experimentally the phenomenon of spontaneous symmetry breaking of strongly localized nonlinear optical modes at the microwatt level in a one-dimensional photonic lattice with a single coupling defect.
T2  - Physical Review A
T1  - Spontaneous symmetry breaking of gap solitons in defect-loaded uniform one-dimensional photonic lattices
VL  - 88
IS  - 2
DO  - 10.1103/PhysRevA.88.023858
ER  - 

@article{
author = "Beličev, Petra and Ilic, Igor and Stepić, Milutin and Hadžievski, Ljupčo and Lou, Cibo and Suntsov, Sergiy and Rueter, Christian E. and Kip, Detlef",
year = "2013",
abstract = "We observe theoretically and experimentally the phenomenon of spontaneous symmetry breaking of strongly localized nonlinear optical modes at the microwatt level in a one-dimensional photonic lattice with a single coupling defect.",
journal = "Physical Review A",
title = "Spontaneous symmetry breaking of gap solitons in defect-loaded uniform one-dimensional photonic lattices",
volume = "88",
number = "2",
doi = "10.1103/PhysRevA.88.023858"
}

Beličev, P., Ilic, I., Stepić, M., Hadžievski, L., Lou, C., Suntsov, S., Rueter, C. E.,& Kip, D.. (2013). Spontaneous symmetry breaking of gap solitons in defect-loaded uniform one-dimensional photonic lattices. in Physical Review A, 88(2).
https://doi.org/10.1103/PhysRevA.88.023858

Beličev P, Ilic I, Stepić M, Hadžievski L, Lou C, Suntsov S, Rueter CE, Kip D. Spontaneous symmetry breaking of gap solitons in defect-loaded uniform one-dimensional photonic lattices. in Physical Review A. 2013;88(2).
doi:10.1103/PhysRevA.88.023858 .

Beličev, Petra, Ilic, Igor, Stepić, Milutin, Hadžievski, Ljupčo, Lou, Cibo, Suntsov, Sergiy, Rueter, Christian E., Kip, Detlef, "Spontaneous symmetry breaking of gap solitons in defect-loaded uniform one-dimensional photonic lattices" in Physical Review A, 88, no. 2 (2013),
https://doi.org/10.1103/PhysRevA.88.023858 . .

TY  - JOUR
AU  - Radovanović, Jelena V.
AU  - Ilic, Igor
AU  - Beličev, Petra
AU  - Milanović, Vitomir B.
AU  - Hadžievski, Ljupčo
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5172
AB  - We present a comparative analysis of the tunneling times of electromagnetic (EM) waves propagating in isotropic and anisotropic media. First, suitable expressions for the tunneling times in a layered periodic material, with anisotropic properties originating from its structure, are derived, followed by numerical calculations performed for a new type of anisotropic semiconductor metamaterial. In the first case, we have considered a layered structure which contains two differently doped In0.53Ga0.47As semiconductor layers. The second structure under investigation is made of alternately placed layers of doped In0.53Ga0.47As and undoped Al0.48Ga0.52As. The investigation of the dwell time as a function of incident wave frequency has revealed the existence of two peaks, one of which may be interpreted as a consequence of anisotropy, while the other one corresponds to the peak related to the absorption and the group delay. Both of these two peaks are affected by variations of layers doping densities. Furthermore, at increased incident angles of incoming EM waves, the dwell time peak occurs at the upper boundary of the frequency interval, for which the structure exhibits negative refractive index.
T2  - Applied Physics. A: Materials Science and Processing
T1  - Comparison of tunneling times in isotropic and anisotropic media
VL  - 109
IS  - 4
SP  - 997
EP  - 1006
DO  - 10.1007/s00339-012-7393-5
ER  - 

@article{
author = "Radovanović, Jelena V. and Ilic, Igor and Beličev, Petra and Milanović, Vitomir B. and Hadžievski, Ljupčo",
year = "2012",
abstract = "We present a comparative analysis of the tunneling times of electromagnetic (EM) waves propagating in isotropic and anisotropic media. First, suitable expressions for the tunneling times in a layered periodic material, with anisotropic properties originating from its structure, are derived, followed by numerical calculations performed for a new type of anisotropic semiconductor metamaterial. In the first case, we have considered a layered structure which contains two differently doped In0.53Ga0.47As semiconductor layers. The second structure under investigation is made of alternately placed layers of doped In0.53Ga0.47As and undoped Al0.48Ga0.52As. The investigation of the dwell time as a function of incident wave frequency has revealed the existence of two peaks, one of which may be interpreted as a consequence of anisotropy, while the other one corresponds to the peak related to the absorption and the group delay. Both of these two peaks are affected by variations of layers doping densities. Furthermore, at increased incident angles of incoming EM waves, the dwell time peak occurs at the upper boundary of the frequency interval, for which the structure exhibits negative refractive index.",
journal = "Applied Physics. A: Materials Science and Processing",
title = "Comparison of tunneling times in isotropic and anisotropic media",
volume = "109",
number = "4",
pages = "997-1006",
doi = "10.1007/s00339-012-7393-5"
}

Radovanović, J. V., Ilic, I., Beličev, P., Milanović, V. B.,& Hadžievski, L.. (2012). Comparison of tunneling times in isotropic and anisotropic media. in Applied Physics. A: Materials Science and Processing, 109(4), 997-1006.
https://doi.org/10.1007/s00339-012-7393-5

Radovanović JV, Ilic I, Beličev P, Milanović VB, Hadžievski L. Comparison of tunneling times in isotropic and anisotropic media. in Applied Physics. A: Materials Science and Processing. 2012;109(4):997-1006.
doi:10.1007/s00339-012-7393-5 .

Radovanović, Jelena V., Ilic, Igor, Beličev, Petra, Milanović, Vitomir B., Hadžievski, Ljupčo, "Comparison of tunneling times in isotropic and anisotropic media" in Applied Physics. A: Materials Science and Processing, 109, no. 4 (2012):997-1006,
https://doi.org/10.1007/s00339-012-7393-5 . .

TY  - JOUR
AU  - Beličev, Petra
AU  - Ilic, Igor
AU  - Maluckov, Aleksandra
AU  - Stepić, Milutin
AU  - Kanshu, Andrey
AU  - Rueter, Christian E.
AU  - Kip, Detlef
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5048
AB  - The existence and stability of spatial solitons in one-dimensional binary photonic lattices with alternating spacing and a saturable defocusing type of nonlinearity are investigated. Five types of nonlinear localized structures are found to exist: two in the mini-gap in the energy spectrum and others in the regular gap. It is proved that some of them are stable in certain ranges of the system parameters. Interactions between two identical localized structures propagating parallel to each other are investigated, too. It is shown that this interaction leads to formation of different localized patterns, such as solitons, breather-like modes, and breather complexes. The interaction output depends on the power and type of interacting identical solitons, the separation between them, the width of the mini-gap, and the phase relation between the tails of interacting solitons.
T2  - Physical Review A
T1  - Dynamics of gap solitons in one-dimensional binary lattices with saturable self-defocusing nonlinearity and alternating spacing
VL  - 86
IS  - 3
DO  - 10.1103/PhysRevA.86.033835
ER  - 

@article{
author = "Beličev, Petra and Ilic, Igor and Maluckov, Aleksandra and Stepić, Milutin and Kanshu, Andrey and Rueter, Christian E. and Kip, Detlef",
year = "2012",
abstract = "The existence and stability of spatial solitons in one-dimensional binary photonic lattices with alternating spacing and a saturable defocusing type of nonlinearity are investigated. Five types of nonlinear localized structures are found to exist: two in the mini-gap in the energy spectrum and others in the regular gap. It is proved that some of them are stable in certain ranges of the system parameters. Interactions between two identical localized structures propagating parallel to each other are investigated, too. It is shown that this interaction leads to formation of different localized patterns, such as solitons, breather-like modes, and breather complexes. The interaction output depends on the power and type of interacting identical solitons, the separation between them, the width of the mini-gap, and the phase relation between the tails of interacting solitons.",
journal = "Physical Review A",
title = "Dynamics of gap solitons in one-dimensional binary lattices with saturable self-defocusing nonlinearity and alternating spacing",
volume = "86",
number = "3",
doi = "10.1103/PhysRevA.86.033835"
}

Beličev, P., Ilic, I., Maluckov, A., Stepić, M., Kanshu, A., Rueter, C. E.,& Kip, D.. (2012). Dynamics of gap solitons in one-dimensional binary lattices with saturable self-defocusing nonlinearity and alternating spacing. in Physical Review A, 86(3).
https://doi.org/10.1103/PhysRevA.86.033835

Beličev P, Ilic I, Maluckov A, Stepić M, Kanshu A, Rueter CE, Kip D. Dynamics of gap solitons in one-dimensional binary lattices with saturable self-defocusing nonlinearity and alternating spacing. in Physical Review A. 2012;86(3).
doi:10.1103/PhysRevA.86.033835 .

Beličev, Petra, Ilic, Igor, Maluckov, Aleksandra, Stepić, Milutin, Kanshu, Andrey, Rueter, Christian E., Kip, Detlef, "Dynamics of gap solitons in one-dimensional binary lattices with saturable self-defocusing nonlinearity and alternating spacing" in Physical Review A, 86, no. 3 (2012),
https://doi.org/10.1103/PhysRevA.86.033835 . .

TY  - JOUR
AU  - Radovanovic, Jelena V.
AU  - Ilic, Igor
AU  - Beličev, Petra
AU  - Hadžievski, Ljupčo
AU  - Milanović, Vitomir B.
PY  - 2011
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4312
AB  - Investigating the propagation of electromagnetic radiation in linear and nonlinear materials (with third-order nonlinearity), we derived a general expression for the dwell time valid for all linear media, as well as its relation with the group delay. The obtained results indicate that, for a nonmagnetic lossless material, the group delay reduces to the sum of the dwell time and the self-interference time. Calculations confirmed the occurrence of the Hartman effect in negative-refractive-index metamaterials (the dwell time saturates with increasing obstacle length), as well as the negative group delay in a certain spectral regime. Analysis of the Goos-Hanchen shift, in case of an obstacle made of negative-refractive-index metamaterial embedded in a dielectric with saturable nonlinearity, showed that there is no impact on the dwell time, while various effects on the group delay may be achieved, including its reduction or even preservation for nonzero incident angles. (C) 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3586782]
T2  - Journal of Nanophotonics
T1  - Tunneling times in dispersive and third-order nonlinear optical metamaterials
VL  - 5
DO  - 10.1117/1.3586782
ER  - 

@article{
author = "Radovanovic, Jelena V. and Ilic, Igor and Beličev, Petra and Hadžievski, Ljupčo and Milanović, Vitomir B.",
year = "2011",
abstract = "Investigating the propagation of electromagnetic radiation in linear and nonlinear materials (with third-order nonlinearity), we derived a general expression for the dwell time valid for all linear media, as well as its relation with the group delay. The obtained results indicate that, for a nonmagnetic lossless material, the group delay reduces to the sum of the dwell time and the self-interference time. Calculations confirmed the occurrence of the Hartman effect in negative-refractive-index metamaterials (the dwell time saturates with increasing obstacle length), as well as the negative group delay in a certain spectral regime. Analysis of the Goos-Hanchen shift, in case of an obstacle made of negative-refractive-index metamaterial embedded in a dielectric with saturable nonlinearity, showed that there is no impact on the dwell time, while various effects on the group delay may be achieved, including its reduction or even preservation for nonzero incident angles. (C) 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3586782]",
journal = "Journal of Nanophotonics",
title = "Tunneling times in dispersive and third-order nonlinear optical metamaterials",
volume = "5",
doi = "10.1117/1.3586782"
}

Radovanovic, J. V., Ilic, I., Beličev, P., Hadžievski, L.,& Milanović, V. B.. (2011). Tunneling times in dispersive and third-order nonlinear optical metamaterials. in Journal of Nanophotonics, 5.
https://doi.org/10.1117/1.3586782

Radovanovic JV, Ilic I, Beličev P, Hadžievski L, Milanović VB. Tunneling times in dispersive and third-order nonlinear optical metamaterials. in Journal of Nanophotonics. 2011;5.
doi:10.1117/1.3586782 .

Radovanovic, Jelena V., Ilic, Igor, Beličev, Petra, Hadžievski, Ljupčo, Milanović, Vitomir B., "Tunneling times in dispersive and third-order nonlinear optical metamaterials" in Journal of Nanophotonics, 5 (2011),
https://doi.org/10.1117/1.3586782 . .

TY  - JOUR
AU  - Beličev, Petra
AU  - Ilic, Igor
AU  - Stepić, Milutin
AU  - Maluckov, Aleksandra
AU  - Tan, Yang
AU  - Chen, Feng
PY  - 2010
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4102
AB  - We investigate light localization at a single phase-slip defect in one-dimensional photonic lattices, both numerically and experimentally. We demonstrate the existence of various robust linear and nonlinear localized modes in lithium niobate waveguide arrays exhibiting saturable defocusing nonlinearity. (C) 2010 Optical Society of America
T2  - Optics Letters
T1  - Observation of linear and nonlinear strongly localized modes at phase-slip defects in one-dimensional photonic lattices
VL  - 35
IS  - 18
SP  - 3099
EP  - 3101
DO  - 10.1364/OL.35.003099
ER  - 

@article{
author = "Beličev, Petra and Ilic, Igor and Stepić, Milutin and Maluckov, Aleksandra and Tan, Yang and Chen, Feng",
year = "2010",
abstract = "We investigate light localization at a single phase-slip defect in one-dimensional photonic lattices, both numerically and experimentally. We demonstrate the existence of various robust linear and nonlinear localized modes in lithium niobate waveguide arrays exhibiting saturable defocusing nonlinearity. (C) 2010 Optical Society of America",
journal = "Optics Letters",
title = "Observation of linear and nonlinear strongly localized modes at phase-slip defects in one-dimensional photonic lattices",
volume = "35",
number = "18",
pages = "3099-3101",
doi = "10.1364/OL.35.003099"
}

Beličev, P., Ilic, I., Stepić, M., Maluckov, A., Tan, Y.,& Chen, F.. (2010). Observation of linear and nonlinear strongly localized modes at phase-slip defects in one-dimensional photonic lattices. in Optics Letters, 35(18), 3099-3101.
https://doi.org/10.1364/OL.35.003099

Beličev P, Ilic I, Stepić M, Maluckov A, Tan Y, Chen F. Observation of linear and nonlinear strongly localized modes at phase-slip defects in one-dimensional photonic lattices. in Optics Letters. 2010;35(18):3099-3101.
doi:10.1364/OL.35.003099 .

Beličev, Petra, Ilic, Igor, Stepić, Milutin, Maluckov, Aleksandra, Tan, Yang, Chen, Feng, "Observation of linear and nonlinear strongly localized modes at phase-slip defects in one-dimensional photonic lattices" in Optics Letters, 35, no. 18 (2010):3099-3101,
https://doi.org/10.1364/OL.35.003099 . .

TY  - JOUR
AU  - Beličev, Petra
AU  - Ilic, Igor
AU  - Milanović, Vitomir B.
AU  - Radovanović, Jelena V.
AU  - Hadžievski, Ljupčo
PY  - 2009
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3781
AB  - Tunneling times of electromagnetic planar wave propagating through a barrier made of split-ring resonators and long metallic wires embedded into a dielectric with saturable nonlinearity are analyzed. For such structure, analytical expressions for the tunneling times and relation between the group delay and the dwell time are obtained. The electric-field distribution inside the barrier is numerically evaluated and a detailed study of the influence of nonlinearity on the spectral structures of the tunneling times is performed. It is demonstrated that intensity variation in the incident field may change the wave propagation direction, the sign of the barriers refractive index, and group delay.
T2  - Physical Review A
T1  - Tunneling times in metamaterials with saturable nonlinearity
VL  - 80
IS  - 2
DO  - 10.1103/PhysRevA.80.023821
ER  - 

@article{
author = "Beličev, Petra and Ilic, Igor and Milanović, Vitomir B. and Radovanović, Jelena V. and Hadžievski, Ljupčo",
year = "2009",
abstract = "Tunneling times of electromagnetic planar wave propagating through a barrier made of split-ring resonators and long metallic wires embedded into a dielectric with saturable nonlinearity are analyzed. For such structure, analytical expressions for the tunneling times and relation between the group delay and the dwell time are obtained. The electric-field distribution inside the barrier is numerically evaluated and a detailed study of the influence of nonlinearity on the spectral structures of the tunneling times is performed. It is demonstrated that intensity variation in the incident field may change the wave propagation direction, the sign of the barriers refractive index, and group delay.",
journal = "Physical Review A",
title = "Tunneling times in metamaterials with saturable nonlinearity",
volume = "80",
number = "2",
doi = "10.1103/PhysRevA.80.023821"
}

Beličev, P., Ilic, I., Milanović, V. B., Radovanović, J. V.,& Hadžievski, L.. (2009). Tunneling times in metamaterials with saturable nonlinearity. in Physical Review A, 80(2).
https://doi.org/10.1103/PhysRevA.80.023821

Beličev P, Ilic I, Milanović VB, Radovanović JV, Hadžievski L. Tunneling times in metamaterials with saturable nonlinearity. in Physical Review A. 2009;80(2).
doi:10.1103/PhysRevA.80.023821 .

Beličev, Petra, Ilic, Igor, Milanović, Vitomir B., Radovanović, Jelena V., Hadžievski, Ljupčo, "Tunneling times in metamaterials with saturable nonlinearity" in Physical Review A, 80, no. 2 (2009),
https://doi.org/10.1103/PhysRevA.80.023821 . .

TY  - JOUR
AU  - Ilic, Igor
AU  - Beličev, Petra
AU  - Milanović, Vitomir B.
AU  - Radovanović, Jelena V.
PY  - 2008
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3585
AB  - Tunneling times in absorptive and dispersive media are considered, as are the relations between them. Group delay and dwell time are used as the most appropriate tunneling time characterizations. A general expression that relates these two quantities, valid for all linear media (with both positive and negative index of refraction), is derived, but particular attention is given to negative index metamaterials. The example of a nonmagnetic, lossless medium with dispersive surroundings was chosen to illustrate the derivation of self-interference time. Existence of the Hartman effect and negative group delay in a certain range of frequencies, in metamaterials, is numerically verified. (C) 2008 Optical Society of America
T2  - Journal of the Optical Society of America. B: Optical Physics
T1  - Analysis of tunneling times in absorptive and dispersive media
VL  - 25
IS  - 11
SP  - 1800
EP  - 1804
DO  - 10.1364/JOSAB.25.001800
ER  - 

@article{
author = "Ilic, Igor and Beličev, Petra and Milanović, Vitomir B. and Radovanović, Jelena V.",
year = "2008",
abstract = "Tunneling times in absorptive and dispersive media are considered, as are the relations between them. Group delay and dwell time are used as the most appropriate tunneling time characterizations. A general expression that relates these two quantities, valid for all linear media (with both positive and negative index of refraction), is derived, but particular attention is given to negative index metamaterials. The example of a nonmagnetic, lossless medium with dispersive surroundings was chosen to illustrate the derivation of self-interference time. Existence of the Hartman effect and negative group delay in a certain range of frequencies, in metamaterials, is numerically verified. (C) 2008 Optical Society of America",
journal = "Journal of the Optical Society of America. B: Optical Physics",
title = "Analysis of tunneling times in absorptive and dispersive media",
volume = "25",
number = "11",
pages = "1800-1804",
doi = "10.1364/JOSAB.25.001800"
}

Ilic, I., Beličev, P., Milanović, V. B.,& Radovanović, J. V.. (2008). Analysis of tunneling times in absorptive and dispersive media. in Journal of the Optical Society of America. B: Optical Physics, 25(11), 1800-1804.
https://doi.org/10.1364/JOSAB.25.001800

Ilic I, Beličev P, Milanović VB, Radovanović JV. Analysis of tunneling times in absorptive and dispersive media. in Journal of the Optical Society of America. B: Optical Physics. 2008;25(11):1800-1804.
doi:10.1364/JOSAB.25.001800 .

Ilic, Igor, Beličev, Petra, Milanović, Vitomir B., Radovanović, Jelena V., "Analysis of tunneling times in absorptive and dispersive media" in Journal of the Optical Society of America. B: Optical Physics, 25, no. 11 (2008):1800-1804,
https://doi.org/10.1364/JOSAB.25.001800 . .