Doktorandenseminar

Das Doktorandenseminar des SFB findet jede zweite Woche donnerstags 14:50 - 16:20 Uhr statt. Der Raum wird in der Rundmail bekanntgegeben. Im Anschluss gibt es die Möglichkeit die Themen bei einer Tasse Tee oder Kaffee weiter zu erörtern.

2025

Datum	Vortragende	Titel des Vortrages
16.01.2025	Gustavo Lombardi (MPI-CPfS) Chair: Francisco Lieberich	"Probing the 4f role on the ground state of heavy fermion superconductors"
13.02.2025	Alexander Schwenke	"The Numerical Linked Cluster Expansion for frustrated quantum magnets"
27.02.2025	Annarose Jose Palliyan	"Synthesis, crystal growth and magnetic properties of some oxide"
27.03.2025	Sabastian Granberg Cauchi	"A chiral spin liquid meets a magnet: the decorated-honeycomb Kitaev model in an external field"
24.04.2025	Nico Albert	"Introduction to Open Quantum Systems and Dissipative Phase Transitions"
08.05.2025	Justus Grumbach	"Dilatometry: Measure length – know magnetism?"
22.05.2025	Manuel Schulze	"Overview talk about crystal growth methods with lab tour"
24.06.2025	Oleksandr Zaiets	"Transmission electron microscopy" with lab tour
03.07.2025	Dr. Daniel Lozano-Gómez Chair: Niccolò Francini	"Introduction to magnetic pyrochlores: general models, magnetic phases, and approaches to study them"
17.07.2025	Felix Seewald	"Local Probes and Altermagnetism"
31.07.2025	Hannah Price	tba
12.08.2025	Eva Lopez Rojo	tba
28.08.2025	Charlotte Beneke	tba
09.09.2025		Barbecue
09.10.2025	Julia Besproswanny	tba
23.10.2025	Fabian Köhler	tba

2024

Datum	Vortragende	Titel des Vortrages
12.12.2024 1pm GER/37/H	Prof. Carsten Timm	"Scientific Writing"
28.11.2024	Prof. Alexey Chernikov	"Live by the sword: Handling the paper review/revision/rebuttal"
21.11.2024	Tom Drechsler	"QMCalc - A computer algebra based package for solid state physicists"
14./15.11.24	SFB 1143 Herbstschule 2024
18.10.2024	PhD Symposium
05.09.2024	Oleksandr Zaiets	"Determination of Magnetic Symmetries by Convergent Beam Electron Diffraction"
08.08.2024	Charlotte Beneke	"An Introduction to Field-Theoretic Renormalization Group Theory on the Example of an Exciting Impurity Problem"
25.07.2024	Manuel Schulze	"A previously unnoticed RE-TM-antimonide: CeFeSb₃"
11.07.2024	Niccolò Francini	"Brief guide to Markov chain Monte-Carlo"
27.06.2024	Prof. Dr. Matthias Vojta (TUD/ITP)	"DFG Proposal Writing"
13.06.2024	Martin Rotter Chair: Justus Grumbach	"Adiabatic Approximation and Magnetism - Crystal Field Phonon Interactions in McPhase"
03./04.06.2024	SFB Retreat 2024
30.05.2024	Tillmann Weinhold	"Study of Topologic Materials by Magnetic Resonance Techniques"
16.05.2024	Julia Besproswanny	"STM studies on the Weyl-semimetal and superconductor trigonal PtBi₂"
11.04.2024	Miranda Vinay (Associate Editor Springer Nature, Germany)	Online Workshop on Scientific Writing
07.03.2024	Andy Thomas (IFW) Sebastian Beckert	"In-situ Correlation of Electrical (Magneto-)Transport Effects with Magnetic Textures in a Transmission Electron Microscope"
22.02.2024	Felix Seewald (TUD/IFMP)	"Mössbauer spectroscopy on frustrated systems"
15.02.2024	Nicola Poccia (IFW) Chair: Tsuei-Shin	"Innovative tools for quantum materials exploration: the case of twisted bilayers cuprate heterostructures"
08.02.2024	Carl Lehmann (TUD/ITP)	"Non-Hermitian Phenomena in Closed Correlated Fermionic Systems"
25.01.2024	Francisco Lieberich (MPI-CPfS)	"Elastocaloric effect of SrCu₂(BO₃)₂ under uniaxial pressure"
19.01.2024 9:20 am HSZ/301/U	Michael Scherer (Ruhr Universität Bochum) Chair: David Moser	"Competing interactions, phase transitions, and criticality in 2D Dirac systems"
11.01.2024	Tom Drechsler (TUD/ITP)	"Group Representations - An Introduction"

2023

Datum	Vortragende	Titel des Vortrages
19.12.2023	Social event: Christmast market
07.12.2023	Michel Miranda	"Kondo screening in Kitaev spin liquids with a Fermi surface"
23.11.2023	Roderich Moessner (MPI-PKS)	"Fluctuation induced ordering on the kagome lattice"
09.11.2023	Goran Nakerst	"Introduction to Julia - A programing tutorial"
2./3.11.2023	SFB Herbstschule 2023
05.07.2023
05.07.2023	9:00 - 13:00 Workshop "Stressmanagement" by Katharina Ulbrich (GA TU Dresden) at GA basement area, room 4
08.06.2023	Tutorial-Tag am IFW Vortrag Dr. Sabine Wurmehl: “Crystal growth techniques as tool towards complex novel materials in solid state research” Guided lab tour Chair: David Moser
01.06.2023	Tutorial-Tag am MPI-CPfS Vortrag Chandra & Menges: “Crystals growth and transport properties of topological materials” Guided lab tour Chair: Fabian Köhler
25.05.2023	Jun.-Prof. Hong-Hao Tu	"Possible chiral spin liquid state in the spin-1/2 kagome Heisenberg model"
04.05.2023	Kerstin Brankatschk	Allgemeine Information zum Graduiertenkolleg, sowie zu wichtigen SFB 1143 Veranstaltungen 2023

2022

Datum	Vortragende	Titel des Vortrages
01.12.2022	Nikolaos Stefanidis (MPI-PKS) Chair: Aswathi Mannathanath	"Excitonic Laughlin states in MATBG and the higher Landau levels of graphene"
20.10.2022	Chair: Pedro Consoli	"Kondo breakdown transitions and phase-separation tendencies in valence-fluctuating heavy-fermion metals"
15.09.2022	Andy Knoll (TUD/ITP)	Screening in Weyl semimetals
07.09.2022	Dr. Ranjith Kumar (IFW) Chair: Sreejith Thamban	"NMR evidence against spin-nematic nature of the presaturation phase in frustrated magnet SrZnVO(PO₄)"
30.06.2022	Chair: Bastian Beckert	“Magneto-thermal transport in non collinear antiferromagnetic thin films”
09.06.2022	Pablo Pedrazzini (CONICET & Universidad Nacional de Cuyo) Chair: Michel Miranda	“Metamagnetism in CeTiGe alloys”
18.05.2022	Tutorial-Tag am HZDR Vortrag Sven Luther: “Magnetometric exploration of the phase diagrams of Yb-based delafossites” Guided lab tour Chair: Andreas Hauspurg (HZDR)
12.05.2022	Wilhelm Krüger (TUD/ITP)	"Modeling the honeycomb magnet Na₂Co₂TeO₆: Significance of ring exchange"
31.03.2022	Chair: Abanoub Hanna	"Crystal growth and characterization of the spin-liquid candidate PbCuTe₂O₆^"

2021

Datum	Vortragende	Titel des Vortrages
09.12.2021	Steffen Sykora (TUD/ITP) Chair: Konstantinos Ladovrechis	“Generalized diagonalization scheme of the Kondo model”
25.11.2021	Chair: Erik Wagner	“The J_1-J_2-Heisenberg Bilayer"
28.10.2021	Bernhard Frank (TUD/ITP) Chair: Charlotte Beneke	"Thermodynamics and Transport without Quasiparticles - From the unitary Fermi gas to quantum critical metals-"
30.09.2021	Hua-Chen Zhang Chair: Sreejith Chulliparambil	"Chiral conformal field theory for topological states and the anyon eigenbasis on the torus"
02.09.2021	Chair: Sukriti Singh
21.06.2021	Dr. Willian Natori (Institut Laue-Langevin, Grenoble, France) Chair: Pedro Consoli	"Local Probes for Charge-Neutral Edge States in Two-Dimensional Quantum Magnets"
03.06.2021	João Carlos de Andrade Getelina (São Carlos Institute of Physics, Brazil) Chair: Michel Miranda	"A mean-field approach to the superfluid-Mott glass phase transition"
20.05.2021	Ekaterina Vinokurova (TUD/IFMP)	"Dilution of α-RuCl₃ by Non-Magnetic Elements: Synthesis and Crystal Growth"
06.05.2021	Bastian Rubrecht (IFW)	"Probing MnBi₄Te₇ under hydrostatic pressure"
25.03.2021	Konstantinos Ladovrechis (TUD/ITP)	"Competing magnetic orders and multipolar Weyl fermions in 227 pyrochlore iridates"
12.03.2021	Sreejith Chulliparambil (TUD/ITP)	"Flux crystals, Majorana metals and flat bands in exactly solvable spin-orbital liquids"
25.02.2021	Erik Wagner (BS)	"Two triplon excitations of the Kitaev-Heisenberg-Bilayer"
11.02.2021	Alberto Corticelli (MPI-PKS)	"Spin-Space Groups and Magnon Band Topology"
28.01.2021	Wilhelm Krüger (TUD/ITP)	"Renormalization group analysis for the Kitaev model at intermediate fields"
21.01.2021	Matthias Gillig (IFW)	"Low-temperature thermal transport in the spin-liquid candidate NaYbS₂"

2020

Datum	Vortragende	Titel des Vortrags
17.12.2020	Andreas Hauspurg (HZDR)	"Acoustic waves - a sensitive and powerful tool in experimental solid state physics"
03.12.2020	Charlotte Beneke (TUD/ITP)	Introductory Talk
19.11.2020	Andy Knoll (TUD/ITP)	"Negative longitudinal magnetoconductance at weak fields in Weyl semimetals"
05.11.2020	Heike Eisenlohr (TUD/ITP)	"LiHoF₄ in tilted fields: emergent mesoscale antiferromagnetism near ferromagnetic transverse-field criticality"
22.10.2020	Tom Klaproth (IFW)	"Photoemission electron microscopy (PEEM) as a tool to study electronic properties of 2D materials"
08.10.2020	Prof. Dr. Matthias Vojta (TUD/ITP)	"DFG Proposal Writing"
14.07.2020	Prof. Dr. Carsten Timm (TUD/ITP)	"Scientific Writing"
02.07.2020	Ellen Häußler (TUD/CHE)	"Synthesis of magnetic layered materials"
25.06.2020	Sukriti Singh (MPI-CPfS)	"Single crystal growth and study of some selective topological superconductors and ferromagnets"
18.06.2020	Prof. Dr. Dmytro Inosov (TUD/IFMP)	"Proposal Writing"
12.03.2020	Lorenzo Pastori (TUD/ITP)	"Disentangling sources of quantum entanglement in quench dynamics"
27.02.2020	Bastian Rubrecht (IFW)	"LRO in the triangular lattice AFM KCeS₂"
30.01.2020	Luis Colmenarez (MPI-PKS) Chair: Madelynn Nayga	"Statistics of correlations functions in the random Heisenberg chain"
16.01.2020	Gerald Malsch (TUD/IAP)	"Choosing the right colour scale for data presentation"

2019

Datum	Vortragende	Titel des Vortrags
21.11.2019	Christoph Wellm (IFW) Chair: Matthias Gillig (IFW)	"Electron spin resonance studies on the putative spin liquid compound Na₂BaCo(PO₄)₂"
07.11.2019	Dr. Pabitra Kumar Biswas (STFC Rutherford Appleton Laboratory, UK) Chair: Shreenanda Ghosh	"Muon spin spectroscopy studies of Fe-chalchogenide superconductors"
24.10.2019	Renato Dantas (MPI-PKS) Chair: Heike Eisenlohr	"Non‐Abelian anomalies in multi‐Weyl semimetals"
29.08.2019	Ciarán Hickey (Universität Köln) Chair: Urban Seifert	"Field-Induced Phenomena in Kitaev Magnets"
08.08.2019	Prof. Dr. Satoru Nakatsuji (University of Tokyo) Chair: Yulia Gritsenko	"Topological spintronics using frustrated magnets"
18.07.2019	Charlotte Beneke (TUD/ITP)	Introductory Talk
04.07.2019	Dr. Thomas Herrmannsdoerfer (HZDR) Chair: Shanu Dengre	"Investigation of pyrochlore compounds at extreme sample conditions"
27.06.2019	Dr. Silvia Viola Kusminskiy (MPI-for the science of light) Chair: Urban Seifert	"Cavity Optomagnonics"
20.06.2019	Dr. Jeffrey Rau (MPI-PKS) Chair: Heicke Eisenlohr	"Topological magnons and the non-Hermitian topology of spontaneous magnon decay"
09.05.2019	Dr. Steffen Sykora (IFW) Chair: Christoph Wuttke	"Many-particle approach to a model of nematic fluctuations in orin-based superconductors"
25.04.2019	Chair: Heike Eisenlohr	Einführungsvorträge 3 "neuer" Doktoranden
11.04.2019	Dr. Tiago Mendes Santos (ICTP, Italy) Mary Madelynn Nayga	"Measuring entanglement in many-body systems via thermodynamics"
14.03.2019	Gizem Aslan Cansever (IFW)	"Addressing controversial findings on the magnetism of Sr₂YIrO₆: the case of Y to Ir ratio"
28.02.2019	Yevhen Onykiienko (TUD/IFMP)	"Neutron scattering. Under the hood"
14.02.2019	Dr. David Luitz (MPI-PKS) Chair: Heike Eisenlohr	"Out of time order correlators and locality in quantum many-body systems"
31.01.2019	Felix Brückner (TUD/IFMP)	"Spin freezing in disordered pyrochlore magnets probed by NMR"
17.01.2019	Chair: Heike Eisenlohr	Einführungsvorträge 3 "neuer" Doktoranden

2018

Datum	Vortragende	Titel des Vortrags
11.12.2018		Weihnachtsfeier
27.11.2018	Oleg Petrenko (University of Warwick, UK) Chair: Yulia Gritsenko (HZDR)	"Low-temperature in-field behavior of magnetic systems with frustrated interactions"
08.11.2018	Chris Koschenz (TUD/ITP)
25.10.2018	Stephanie Matern (St. Andrews, UK) Chair: Laura Köhler (TUD/ITP)	"Memory effects in a simple metal"
11.10.2018	Rodriguez Beltran
13.09.2018/ 14.09.2018		DFG-Begutachtung
21.08.2018/ 22.08.2018	Sommerschule und 4. Klausurtagung im Parkhotel Meißen
19.07.2018	Prof. Chris Ling Chair: Lisa Leissner	"Modulated order in solid-state ionic conductors: a fine line between helping and hindering"
21.06.2018	Wei Tang (Peking University) Chair: Lorenzo Pastori (TUD/ITP)	"Universal entropy of conformal critical theories on a Klein bottle: a quantum Monte Carlo study"
07.06.2018	Tutorial -Tag des ITP: Introduction to theoretical methods in frustrated systems 1.30 - 3.00 pm - Jun.-Prof. Hong-Hao Tu (TUD/ITP) - Introduction to Matrix Product States 3.00 - 3.30 pm - Kaffeepause 3:30 - 5 pm - Dr. Lukas Janssen (TUD/ITP) - Introduction to Heisenberg - Kitaev physics in magnetic fields Chair: Angelo Pidatella (TUD/ITP)
17.05.2018	Dr. Federico Caglieris (IFW) Chair: Johannes Schoop (IFW)	"Giant anomalous Nernst effect in Weyl Semimetals"
03.05.2018	Benjamin Wolba (TUD/ITP)	"Phasediagram of Chiral Antiferromagnets"
19.04.2018	Dr. Inti Sodemann (MPI-PKS) Chair: Urban Seifert (TUD/ITP)	"Quantum Phase Transitions in the Half Filled Landau Level"
05.04.2018		First Symposium of the PhD-program in Correlated Magnetism
22.02.2018	Prof. Jan Budich (TUD/ITP) Chair: Santanu Dey (TUD/ITP)	"Nonequilibrium Dynamics in Topological Insulators"
08.02.2018	Kerstin Brankatschk	Allgemeine Information zum Graduiertenkolleg, sowie zu wichtigen SFB 1143 Veranstaltungen 2018
11.01.2018	Chair: Thomas Stöter (TUD/IFMP & HZDR)	Lightning talks about PhD-projects

2017

Datum	Vortragende	Titel des Vortrags
11.12.2017		Weihnachtsfeier
30.11.2017	Chair: Thomas Stöter (TUD/IFMP & HZDR)	Lightning talks about PhD-projects
16.11.2017	Prof. Johannes Reuther FU Berlin Chair: Urban Seifert (TUD/ITP)	"A functional renormalization-group approach for frustrated quantum spin-systems"
02.11.2017	Prof. Riccardo Mazzarello RWTH Aachen Chair: Angelo Pidatella (TUD/ITP)	"Edge magnetism in Graphene NanoRibbons intercating with Topological Insulators"
18. - 19.09.2017	Sommerschule im Berghotel Bastei
30. - 31.08.2017	Klausurtagung im Hotel Kloster Nimbschen (Grimma)
13.07.2017	Dr. Michael Nicklas (MPI-CPfS) Chair: Sascha Albert Bräuninger + Shanu Dengre	"Pressure tuning of material properties: Study of novel unconventional phases"
22.06.2017	Prof. Gang Cao (Boulder) Chair: Michael Vogl	"The Challenge of Spin-Orbit-Tuned Ground States in Iridates"
08.06.2017	Tutorial Day am IFW: 14:00 - 14:50 Prof. Matthias Vojta (TUD/IFW) – Quantum Spin Ice 15:00 - 15:45 „5 minutes talks“ about current progress of the SFB PhDs 15:50 - 16:10 Johannes Schoop - Introduction to e-beam lithographie 16:20 - 17:30 Hands on Exercises and Lab Tour 17:30 – open end BBQ at the IFW courtyard Chair: Haijiao Hu, Johannes Schoop + Michael Vogl
18.05.2017	Tutorial Day am IFW: 1.30 - 3.00 pm – Prof. van den Brink (IFW/TUD) - Kitaev materials - Iridates and RuCl₃ 3.20 - 4.50 pm - Paula L.-Kelley (Oakridge National Lab/ University of Tennessee) - Observation of fractionalized quasiparticles near a quantum spin liquid 5.00 - 5.20 pm - Richard Hentrich - Large field-induced gap of Kitaev-Heisenberg paramagnons in α-RuCl₃ 5:30 - 5.50 pm - Maximilian Geyer - Anisotropic Ru³⁺ magnetism in the honeycomb system α-RuCl₃ 6 pm - Lab Tour and BBQ Chair: Maximilian Geyer + Richard Hentrich
20.04.2017	Dr. Karin Everschor-Sitte Leiterin der Emmy Noether Forschungsgruppe “TWIST – Topological Whirls In SpinTronics” an der Johannes Gutenberg-Universität Mainz Chair: Laura Köhler (TUD/ITP)	„Introduction to magnetic skyrmions – topological magnetic textures”
06.04.2017	Dr. Tobias Meng (TUD/ITP) Chair: Santanu Dey (TUD/ITP)	"Cutting electrons apart: a simple introduction to fractionalization"
06.04.2017	Dr. Tobias Meng (TUD/ITP) Chair: Santanu Dey (TUD/ITP)	"Cutting electrons apart: a simple introduction to fractionalization"
09.03.2017	Tutorial-Tag an der TUBAF (Freiberg) Dr. Christian Schimpf Institut für Werkstoffwissenschaft/ Technische Universität Bergakademie Freiberg Chair: Lisa Leißner + Mathis Antlauf	- Vortrag zum Thema Rietveld-Verfeinerung an Pulverdiffraktometriedaten - Experimente und Führung durch das XRD-Labor - Diskussion zum Thema
09.02.2017	Thomas Stöter	"Experimental evidence of Spin Ice Behaviour in Dy₂Ti₂O₇"
09.02.2017	Dr. Mathias Dörr (TUD/IFMP)	"Theory and Experiment of Magnetostriction and Thermal Expansion"
26.01.2017	Chair: Thomas Stöter	Lightning Talks
12.01.2017	IFW Raum D2E.32	Planung des Doktorandenseminars 2017

2016

Datum	Vortragende	Titel des Vortrags
07.12.2016		Arbeitsgruppentreffen mit Weihnachtsfeier
24.11.2016, 15 Uhr		Planung des Jahres 2017 IFW Raum D2E.32
09.11.2016		Arbeitsgruppentreffen
27.10.2016, 15 Uhr	Prof. Matthias Vojta (TUD/ITP)	Spin Ice: Frustration, Monopoles, Phase Transitions IFW Raum D2E.32
12.10.2016		Arbeitsgruppentreffen
28.09.2016		Arbeitsgruppentreffen
14.09.2016	Dr. Markus Schwarz (TU Bergakademie Freiberg)	Tutorial-Tag an der TUBAF (Freiberg): Vortrag zum Thema "High Pressure Synthesis" sowie Campus-Tour, Laborführungen und Arbeit in Kleingruppen
31.08.2016	Dr. Mathias Dörr (TUD/IFMP)
17.08.2016		Arbeitsgruppentreffen
20.07.2016		Arbeitsgruppentreffen
06.07.2016	Hannes Stummer (IFW)	"Crystal characterization with X-rays"
22.06.2016		Arbeitsgruppentreffen
08.06.2016	Maximilian Kusch (IFW)	SQUID
25.05.2016	Thomas Stöter (TUD/IFMP)	"Magnetostriction of rare earth pyrochlores"
11.05.2016	Yuliia Tymoshenko (TUD/IFMP) Hannes Stummer (IFW)	"Neutron scattering techniques for investigation of magnetic excitations" "High pressure synthesis of Ba₃YIr₂O₉"
27.04.2016	Yevhen Onykiienko (TUD/IFMP) Thomas Stöter (TUD/IFMP & HZDR)	"PANDAS library: simple data analysis" a tutorial: "Latex for Posters"
13.04.2016	Lisa Leißner (TUBAF) Thomas Stöter (TUD/IFMP & HZDR)	Tutorial-Tag an der TUBAF (Freiberg) "High pressure/high temperature synthesis of iridates" Tech-Talk: "git: 'a distributed version control system' or 'How to record the evolution of your thesis'"
30.03.2016	Gizem Aslan Cansever (IFW) Yuliia Tymoshenko (TUD/IFMP)	"Sr₂YIrO₆ single and polycrystalline materials with Ir⁵⁺ states"
16.03.2016	Richard Hentrich (IFW) Jorge Rehn (MPI-PKS)	"Thermal conductivity of a 2D honeycomb material" "Coulomb Spin Liquid on the Honeycomb Lattice" 16:00 Uhr Führung durch das Buchmuseum (SLUB Dresden)
02.03.2016	Maximilian Kusch (IFW) Andrey Bolotnikov (TUD/ITP)	Talk about RIXS "Weyl semimetals: some aspects"
17.02.2016	Yang Zhang (IFW) Thomas Stöter (TUD/IFMP & HZDR)	"Large Anomalous hall effect in non-collinear antiferromagnets" "Magnetoelastic properties of the quantum-spin-ice candidate Yb₂Ti₂O₇"
03.02.2016	Yulia Gritsenko (TUD/IFMP & HZDR)	Tutorial/Führung am HZDR (Dresden-Rossendorf) "Ultrasound measurements".
20.01.2016	Shanu Dengre (TUD/IFMP)	"Solid State NMR: a local probe technique"
06.01.2016	Mathis Antlauf (TUBAF/CHE)	"High pressure synthesis and preparation"

2015

Datum	Vortragende	Titel des Vortrags
06.12.2015		Weihnachtsfeier
09.12.2015	Maximilian Geyer (IFW)	"Magnetic and Thermodynamic characterisation of materials by means of SQUID- and PPMS-measurement systems"
25.11.2015	Johannes Schoop (TUD/CTD & IFW) Michael Vogl (TUD/IFW)	"Transport measurements of microsized Single Crystals and Polycrystals" "Synthesis of iridium-based perovskites"
11.11.2015	Haijiao Hu (TUD/CHE)	"Synthesis of magnetic materials with strong spin-orbit coupling"
28.10.2015	Darshan Joshi (TUD/ITP) Sascha A. Bräuninger (TUD/IFP)	"Magnetic quantum phase transitions: Bond-operator theory and spin-wave theory" "Nuclear probes: µSR and Mössbauer spectroscopy on frustrated Materials"
14.10.2015	Thomas Stöter (TUD/IFMP & HZDR) Erik Neuber (TUD/IAP)	"Magnetostriction measurements by Capacitance Dilatometry" "Scanning Probe Microscopy Magnetic Structures and Topological States"